vr noms:

-> S (+monferno, +victini, -necrozma)
medicham has definitely proved itself to be the best breaker in inheritance. incredible power + 120 BP stab in close combat, an extremely powerful espeed and a diverse list of inherits makes medicham the go-to mon to be countered for most teams, often invoking mons like flash fire doublade just to check it through typing. medicham also has ways around its main counters, such as monferno for mega sableye, non-ff doublade, and if it wants to it can run gunk shot to lure tapu fini and tapu bulu over mach punch or sd depending on whether it wants to balance break or stallbreak. this mon really has it all, and although it can be adapted through with offense and checks like marowak-a, gengar and archeops, it still has all of the best qualities of being an insane threat to deal with in inheritance.

-> A+ (+clefairy, +nidoking, +hydreigon, +rampardos)
I would probably call this the best second best steel in inheritance right now. capable of utilizing its interesting typing to shut down mons like magearna and celesteela is no joke, and its magnet pull sets are very strong at removing some very frustrating threats like offensive celesteela. sadly as it is a steel it can be susceptible to magnet pull itself, and that can do in the viability of more defensive sets like hydreigon. not only are torkoal sets ridiculously hard to resist but nidoking sets can also completely pull out some of the checks to those like flash fires and av dragons, either rocking up on them or ice beaming them for up to 40%, negating their regen, making it harder to counter as rocks chip starts to rack up. I would nominate this to S if I were more confident with its capabilities against offensive teams, however I don't personally feel it is consistent enough to warrant one right now.

-> A+ (+gliscor)
this thing has been a pretty considerable threat for a good amount of time. mold breaker rockium z sets are still jamming out against balance cores and as long as buzzwole isn't used as much it can still be noted as a fairly strong utility threat as well. gliscor sets are a more defensive take on garchomp, utilizing its decent speed tier and typing to take on threats like torkoaltran for more bulky offense oriented teams and being able to knock off shed shells on celesteelas for easier baggings with magnet pull. whilst it still has a considerable weakness against bulky water types, it doesn't mean it can't do anything against them, and non-unaware variants will usually get ruined by this mon because of its natural bulk. definitely a rise from me.

-> A+ (+lucario)
quite possibly the most splashable anti-offense mon there is right now. you want threats like landorus-t and comfeygear to stop sweeping your teams? bring this guy, he's hot. marowak-a does an incredible job of staving off threats like these and playing an incredible role in the endgame to a significant degree because of these typing niches and the movepool that kecleon grants, which allow it to effectively ohko a bunch of heavy threats like tapu koko after rocks and mega medicham, as well as the alternate fires like chandelure and salazzle. consider this mon on any team that happens to be offense weak, you will be surprised at how good he is.

-> A (+arcanine, +tornadus-t, -flareon)
doublade being in C+ is a huge joke considering how good this mon is in the current metagame. it's capable of walling practically every physical attacker given the right set, and is a huge pain in the ass to properly break due to it taking the best breakers on so well. tornadus-t variants are superb when momentum is needed, and can provide big benefits over the alternative, persian-a!tapu bulu for offenses that require a medicham or koko pivot. levitate variants are practically guaranteed to take on landorus, and flash fire variants stop medicham even harder than it did before. this mon deserves massive praise for what good it can do for a team and how tightly it compresses roles.

-> A (+sableye)
fini's definitely a good pivot. capable of avoiding the 2hko from mega medicham (albeit barely) and dealing nicely with mons like landorus-t and terrakion (beware of intimidate variants though!) does make fini very valuable for teams right now. sadly it isn't the worlds best fire resist as most of them are able to slice through it with electric or grass coverage, but as a physical pivot fini does a lot that cune wishes it could do.

-> A- (+quagsire, +miltank, +sableye, +xatu, +volbeat)
practically the same as chansey, just without the ability to wall torktran all day without being disadvantaged. certainly a strong specially based pivot that happens to be really tough to take down and prankster support variants can be a big boon for teams without a good special tank. beware of pursuit users however, blissey is a lot more physically frail than chansey was.

-> A-
the alternative special sheer force user. does a damn good job at thrusting through offensive builds in comparison to gengar and co., which are usually broken by mons like marowak-a or medicham. it does a great job of utilizing the assumption that builds are going to have a physically based electric resist due to tapu koko, and absolutely smacks them due to it. lead set is also very annoying and allows koko to go ham because of it. otherwise not really too much to say other than this was going to take a while.

-> B+ (+talonflame)
m-aero's definitely underrated. for one, its brave bird is incredibly tough to resist, especially when boosted, as it cuts through unaware tapu fini as well as suicune if rocks are present. its incredibly high speed and normal resist make it excellent against offense as well, with the best resisting options either requiring a choice scarf user or a pivot like magearna, doublade or bulu. balance doesn't have too much against this guy either, with the best resistances either needing flash fire (through needing to resist medicham) or utilizing intimidate waters as shown above to try and wear it down with recoil - which is probably this mons biggest issue. strong as heck otherwise, definitely a mon to consider if you don't want to spam mega medicham all day.

-> B+ (+persian-a, +slurpuff, +tsareena)
tapu bulu is one heck of a good pivot. for one, fur coat makes it so that even 2x effective moves from the best hitters can be shrugged off, and can be toxiced for considerable chip. whilst this doesn't really have good recovery, the capability for it to be such a good physical tank often means leftovers can heal it back, and parting shot only makes this better so that bulu doesn't have to be pressured too hard if it needs to come back in again. it also happens to be one of the best walls to medicham and tapu koko, like doublade, but with the added bonus of knock off and parting shot, plus less damage against koko and especially so if it ends up being a different variant. likewise with doublade, this mon rocks and you should seriously consider putting it on more offensive teams as a catch-all pivot. tsareena is also a fairly niche slot that can revenge kill these mons because of priority immunity with a choice scarf, further giving reason for its utility. definitely look out for this beast.
drops:

-> A
cune suffers a lot of competition from fini right now because of mega medicham so I'll agree mostly with pigeons on this one. not too much to say about this one other than it doesn't have as wide a range of options that fini does, despite walling more with its main sets.

-> B
don't see too much reason to use this in a metagame filled to the brim with defensive waters. like what does it do other than not have coverage for it, earthquake and do 20? running pika is also a bad idea because of its lack of sd too, and you'll be struggling vs doublade that way too. it's really mediocre in the current metagame where having a strong wallbreaker means almost everything.

-> C
yeah thund is p much outclassed by zera at this point except for a few more points in special attack and a pretty insignificant flying typing. I see no reason to use this over zera, perhaps someone else can convince me otherwise
misc notes:

+arcanine, zygarde
both of these inherits are excellent espeed users and even against pterrain they do very nicely because of lax's gigantic special bulk. cb with arcanine is a very nice utility resistance capable of taking hits from torkoal inherits and just firing back with a ff boosted flare blitz, and potentially throwing out toxic for bulky waters too. zygarde sorta takes a different look on things, being less potent with attacking and resisting power initially but because of coil and tarrows it often invalidates regular resistances like celesteela and waters like non-unaware cune and fini. I would call this S more than I would call heatran S but both aren't too consistent for me to consider it really.

+mew
yeah blocking priority is nice but have you ever hit that celesteela with a +2 thunderbolt and ohkoed? it's certainly satisfying for me. ep also makes this not bait to muk unlike other variants and also takes care of other steels nicely. certainly much better than lelezam for me, that inherit is grossly overrated imo

-> S (rejected) (+sableye, rampardos)
mag's diverse, and it has great power in its comfey set as a revenge killer. but do I think it's S? not really. fires just do this mon in too hard and its low speed and unfortunate typing for sheer force unfortunately means it isn't the ace breaker it could be. and outside of that, like with the other A+ mons I've called S they just aren't consistent enough for me to really categorize them as S ranked. and as for a steel outside of being neutral to focus blast I generally prefer heatran right now as it has a wider list of more powerful inherits that are useful in a metagame where unaware is normal to encounter. honestly don't understand the whole panic around comfeygear rn, it just isn't very powerful and can be just easily resisted by specially defensive mons like lax that just utilize it as setup fodder.