I did one of those tier list things and i wanted to share some of my thoughts about the meta.
Sometimes i feel like dpp is "solved" because we already know what the most consistent teams are. But at the same time, with how many good viable mons, sets, spreads, items and cores there are, i think there's still a lot of room for innovation and creativity.
And now some explanation about my rankings:
S+ :

- I have tar at #1 because it pretty much does something valuable no mather the team you or your opponent are playing (except against physical offense but i dont think it's particularly a good style). It traps consistently the mons you need to trap, hits so hard with cb, dd is always a menace to defensive teams and sand is broken.

- I put rachi at 2 just because the wish protect set is so hard to break. Besides that, it can do anything: Provide utility with rocks, u-turn and paralysis, sweep with cm, revenge kill with scarf, fish for para-flinches with sub, and pretty much it can run any coverage it wants.

- I would've had lati at 2 because not a lot of things can break the defensive set with twave and reflect, but cb tar and rachi are everywhere at the moment so i think 3 is fair. More offensive sets like scarf, specs or life orb are very good but i dont consider them broken.
S- :

- This mon its amazing. Bulky, strong, great typing and it can learn some of the best moves in the game such as rocks, explosion, wisp and taunt. With lefties it's the best rachi counter, sub protect is deadly with tspikes, idk its just a great breaker with a ton of defensive utility.

- Im not as high on loom as i once was. Sure it restricts the builder a lot and the focus + mach set has very limited answers for defensive/balanced teams, but i think good teams have adapted to the annoyances of free sleep and 130 attack. The defensive set is a contender for the most annoying set in dpp ou.

- Obviously reliable spin enables very powerful stuff like zapdos or lefties gyara, and the fantastic speed makes it a very useful mon to answer frail attackers like infernape or gengar. Also, the bulk it has with max hp and twave is enough to break through mons it shouldn't beat like metagross. Offensive sets are really good vs offense.
A+ :
These 4 guys put a lot of strain in the teambuilding process for me, without the right tools they are so hard to take down (or to withstand in the case of gyara).

- I think special attackers have adapted to clef's walling capabilities. It's still very oppresive and with the right move (twave, encore, protect) it will counter what it needs. Clef + lati is and always will be an amazing defensive combo and knock will always force progress against everything besides loom.

- This thing is so fat it can solo a lot of teams once rocks are off. Pretty much beats every ground type that isn't pert or rhyperior, and even then it usually pairs with loom/celebi so it's no problem. Bold zap with twave is the best set in my opinion, but other moves like uturn, toxic or heat wave are also great. It's also one of the best iron head jirachi answers so i'm glad it exists. Spdef or offensive sets can be good too.

- I've seen people put gyara as high as #3. I think as long as you have multiple answers it will rarely get away with the game. Anyways, gyarados is still an incredible mon. Strong, great typing, great ability, twave on a water type is insane, waterfall flinch always has the potential to rob games, what else is to say?

- Spikes are broken, i can't rank skarm any lower just because of that. The thing is, it's hard to build something decent with skarm that isn't stall or hazard stack offense. The meta isn't very kind to skarmory right now; the mags are very common, starmie is everywhere, and twave gyara can more reliably break shed shell or spdef skarm than one would expect. On top of that, special attackers have risen in usage. I think offensive skarm with a resist berry should be used more.
A-:
This next 4 mons are in my opinion great glue for any team, even though they are not as powerful as the above.

- Great scarfer and mixgon is a menace for a lot of teams. My personal favorite is band: it can switch into celebi's twave and uturn for 80-90%, and surprise kill bold zap at under 64% with stone edge or under 57% with outrage.

- Another great scarfer. Decent spinblocker, the defensive set walls physival rachi well enough and nothing besides tran and clef can take both tbolt and wisp. Other sets can be good too since fighting immunes are rare.

- Traps what it needs very consistently. It's very customizable too: Twave, protect, magnet rise, explosion, toxic, sub, hp ice, fire, grass, or even ground paired with a choice scarf. Can be ev'd to be either fast, powerful, bulky (spdef zone is one of my favorites) or a combination of those 3. Plus, with leftovers it gets rid of wish tect rachi for free which is amazing.

- Gliscor is one of those mons you don't think much about until you face it and your team can't kill it. The classic eq roost taunt ice fang set is great but it can successfully run other utility moves such as taunt, rocks, uturn and knock. Sd sets can clean games quite nicely with the right support and i think a lot of experimentation can be done with it's coverage: ice fang, thunder fang, sky attack, stone edge, roost, taunt, uturn, knock, i've even seen night slash for rotom.
B:

- Everybody knows suicune is great vs offense but struggles vs defense and honestly i don't think so. The modest lum lead punishes stall very consistently, with sub you can get a free cm the turn clef or rachi tries to twave (or knock in clef's case), protect scouts trick attempts, rest can give you an opportunity to sweep later after winning a 1v1, roar is very nice with spikes, and honestly, forcing clef, mie, lati or cele to recover can be good enough with the right team composition.

- This hurts me because i used to believe so much in gross. I just don't like all the free tempo it gives to skarm, defensive rotom and zapdos. I know trick iron ball exists but then you forgo eq, mash or boom. It also struggles to keep up rocks vs defensive starmie without tpunch (same problem as before). Right now i believe lefties are almost mandatory on utility sets since you want to consistently beat wish tect rachi. Nevertheless, meta is crazy strong and bulky so it could never be bad. Some sets i like are full spdef (which can live non specs heatran fire blast), rocks eq mash boom with a custap berry, agility eq zen mash or eq zen ice punch and 4 attacks with tpunch.

- Having wisp + taunt is amazing, being ground and fighting immune is great, it's one of the best offensive switches into scizor's cb uturn, almost nothing can take on the sub split life orb set, its great at negating donphan spin, very good pivot into loom with a lum berry, amazing traits all around. On top of that, it can run other cool moves like destiny bond, explosion, trick holding a black sludge or even sucker punch for opposing offense.

- Honestly i don't have much experience using swampert, i don't like the free turn it gives to loom when it clicks rocks/eq, and even when you predict the loom switch later in the game you often don't kill it so you have to do it twice, which is a guessing game i don't like getting into. Aside from that its a fantastic pokemon: Very hard to kill for non-loom offense, best at keeping rocks vs starmie, and more importantly, great against zapdos, tyranitar and jirachi.

- I'm tired of pretending celebi isn't a top 20 pokemon. This thing is so hard to kill without heatran or scizor. Very annoying twave user, great rocker since mie can't click spin for free, very consistent gyara check, best sub passer and it also gets a bunch of good moves like uturn, trick, heal bell, leech seed and setup moves. Speaking of, nasty plot or just plain offensive 3 attacks rocks/twave can be very good. I'm sure someone could make use of moves like healing wish or perish song.

- Strongest mon in the tier. I'm a fan of the dd life orb set with fire punch, outrage and espeed. Mixnite or regular lum dd are very good too.

- Solid all around. Great rocker (not in the lead position imo). The sub petaya set is one of the best wincons. On the other hand, spdef sets are quite versatile even though they are not very slappable.

- I like that people are experimenting more with ape now. In the past i felt the only real set was cc fb/oh uturn + filler with either an expert belt or life orb. I think band is good, sd or nasty plot have plenty of options to mess up with, a lot of cool utility moves like wisp, taunt, slack off and rocks, items like fist plate or charcoal; Overall a lot of potential for customization.

- With the rise of starmie and celebi i find myself using scizor more. Traps some mons better than tar or sometimes you don't want your trapper to setup sand. Sd sets have a lot of roadblocks but they can be great sweepers with the right support. I'm not a fan of occa sd since there's a 25% chance you get burned or critted by jirachi's fire punch.

- Solid rocker. I believe hippo offense could be done but it's hard to build. I think toxic hippo should be used more.

- I don't think the early momentum of rocks + explosion is that good compared to playing a regular 6v6. Still, some teams really value getting up early rocks and preventing the opponent from doing the same, and zelf is the best at doing that. Band can catch off guard some leads. I don't think much of sets outside the lead slot.
C:

- Not as good at spinning as mie and assurance doesn't do enough to rotom on the switch. However, the elephant has other strengths: It's a decent rocker, a great ddtar answer, and packs not very common moves like ice shard, knock or head smash. Good bulky ground all around.

- Pretty much can answer every special attacker that doesn't pack tspikes support. It's also surprisingly bulky on the defensive side (survives +2 gyara waterfall after rocks). Much better rocker than clef. Needs spin but that isn't too bad. Cm or more offensive spreads should be tried more.

- I don't use zong very much. Offensive rocks + 3 attacks has problems keeping up rocks vs mie, it's too weak vs wish tect rachi and doesn't do anything vs defensive teams. Trick Room is an amazing offense killer but the best it can do against stall is to boom on skarm. Having said that, i like the defensive set paired with a different rocker, that way, you can improve your survivability running something like toxic + protect or rest talk.

- I think roserade it's pretty bad, but tspikes are good and rose is the best at setting them so it ends up here. Sleep is great 75% of the time.

- Specs is great, both inside and outside rain. Other sets can be good but i think they are too fishy: Kingdra just isn't bulky or strong enoug. Some cool ways i've seen people use kingdra are SoS's rain dance + yawn in the lead slot and Dridri's sub dd disable.

- I don't think magneton is very good compared to zone. Sure, it role compresses trapping skarm and revenge killing dders, but it's just too frail and not very strong. What i like about magneton is that it can absorb trick in stall compositions.

- With paralysis support this thing is a beast. Sub 3 attacks, sub sd or plain sd 3 attacks are very good sets. It's super bulky too so sometimes your opponent will waste one of their rhyperior answers just to break the sub. You can ev it so standard zapdos hp ice never breaks the sub, then either zap dies or loom dies. In that sense it also can be used to check ddtar since it will take 50'ish% from +1 eq.

- In a way nidoqueen is a better mon with more defensive utility than roserade, but it is a worse tspike setter since mie will spin more easily on it. Despite that, "I crawled" is an amazing team so i need to put some respect on the queen.

- I love the beagle. Just by clicking spore and rocks you are already at a big advantage so i see the spikes as a bonus. 273 speed gets the jump on other offensive leads like skarm so the speed is fine. Other times you get screwed by lum lead guessing games (or uturn into lum pokemon) but that's what you get for playing such aggresive mon.

- Hard to last mon sweep with in today's meta but great as a wallbreaker. With pursuit / spikes support (or both) scarf cc can be very good too. I think it's worth messing with occa, shuca or maybe even lum.

- With machamp's ban i dont find myself using uxie very much. There are a couple of good uxie teams out there so i can't rank it any lower.

- Barely does what it needs to but has one amazing feat: being the best counter to sub twave gyara. Water immunity can be clutch in the structures it fits. I'm not very high on quag but it's good for sure.

- Goated mon at walling offense but complete dead weight vs stall. Offensive milo can be amazing against some teams.

- I don't have much experience using gastro, but from what I've seen it can be quite good. I've seen it take 60% from ape's grass knot and then proceed to sweep with curse, since nothing could break it and it can't be tricked. I've also seen it hit surprisingly hard with special attack investment.

- Awkward to fit, however zf's aboma tar team is pretty good. I'm still waiting for the offensive hail revolution.

- You use this thing pretty much as a worse zong but with twave so it finds itself in defensive paraspam structures. Still, a steel type with that much bulk can never be bad.

- I don't like the high variance it brings to the tier and i can't say for certain how good it is so it stays in the cheese tier for now.
I'm not interested in writing about the guys below, they are very usable but i just don't care enough for them. There are also a couple of mons i still don't know what to think about, i need to see more successful teams using them.
Many thanks if you read everything, i tried to keep it short but i couldn't do it in less words. I've been playing dpp for 3 years now and no matter how annoyed i am at this tier, i always keep coming back. :)