Alright, time to respond to this novel.
Serperior:
"On the one hand it does some crazy things that even the S tiers can't dream of doing, like soloing multiple major fights with leech seed + coil."
Holy hyperbole batman. Scraggy vs. Clay, Brycen, Shauntal, Caitlin, and possibly Grimsley would beg to disagree. Also SD Excadrill solos anything not named Marshall because it was banned in BW for a reason. Also Archeops can sweep Brycen and Skyla.
I was mostly referring to effortlessly soloing N with this, but I might have gone a bit overboard with this comment I admit. Serperior still has an insanely good end-game potential, better than the other two starters I would say.
2. Look at how many A tiers don't need to setup at all for proof... (through Scraggy can get some mileage out of Work Up + Moxie, it likely doesn't need it due to low Speed).
Sure, you can Coil, but that's at level 38. 3/4 of the game is a significant time to go without setup. Also, when even Swoobat hits harder than Serperior...yeah no.
This is not true. Servine gets coil at level 36, so it's essentially a move gained on evolution. Unless you actively avoid as many trainers as possible and neglect the lucky egg, it is very reasonable to hit level 36 at around the celestial tower, just in time for Skyla. It is only one level higher than Skyla's Swanna. '3/4 of the game' is also exaggerated. If you get coil Serpererior before Skyla, you still get 3 gym fights, 4 elite four fights, 2 rival fights and two final boss fights. That's like half of the game still.
No way that swoobat deals more damage than serperior lol. It's best move is air slash compared to Serperiors leaf blade, with essentially the same offensive stat. I really don't get how this low attack stat is such a problem to you. It's low ON PAPER, but that doesn't mean anything if servine can still consistanly get 2-HKO's on random trainers with stab or return. Obviously having high attack is better than having low attack, but 2-HKO'ing by getting enemies in red with the first attack everytime is not better than 2-HKO'ing by getting them in yellow everytime. And even if it does fail to 2-HKO, it is not the end of the world because Serperior is also very bulky so it can take an extra hit if it needs to.
Match-up based. Let's go down the list.
Chili: It can beat the Lillipup. Obviously monkey is bad.
Lenora: You can maybe do stuff here but they will still hit you hard.
Burgh: Dwebble is possible, but the others are a solid no.
Elesa: Torment + Leech Seed? You can't sit there and tell me this is some paragon of efficiency.
Clay: Best matchup, though Excadrill might finish you off.
Skyla: sigh
It's fairly reasonable to assume you might not be evolved at this point with a rounded team. Skyla's highest is 35, and even Cheren doesn't have his starter evolved in your subsequent battle. Why go through this hogwash when I can literally go catch a Joltik and have roasted duck?
Brycen: Maybe Cryagonal? But yeah, don't even try Coil here.
Drayden: Oh look Dragon Tail makes Coil useless.
Shauntal: Decent here due to beating half her team.
Grimsley: Doubtful. Most of his mons have coverage to kill the snake, though you could probably beat Krookodile and lol Liepard but ANYTHING beats Liepard.
Caitlin: Yeah, no.
Marshall: HOW did you set up on him? Throh has Storm Throw which always crits, and tons of other moves can crit.
N: Yeah, your strategy doesn't work in Black. It does work in White though.
Ghetsis: You got lucky. You can't tell me that's an efficient way to kill Hydriegon when Fighting types exist.
Ok, so once again you are listing what the matchups would look like on paper, but it is really not like that in practice. At least not for me.
Chili: agree. It beats lilipup and does so-so against the monkey. You get your own monkey for free though so this is really not a problem.
Lenora: it two-shots herdier, taking one take down in return. Switch to pampour to avoid retaliate. In my experience, Watchog tries to spam hypnosis until you are asleep, which servine can take advantage of with a chesto berry and leaf tornado accuracy drops. Overall, servine is pretty useful here.
Burgh: you beat Dwebble, but the others are a no-go
Elesa: shitty matchup. I only mentioned Leech seed + torment as a last resort option if you really can't beat her otherwise, but it is definitely not a reliable way of beating her.
Clay: easy solo
Skyla: not sigh, easy solo, for me at least. This matchup is bad on paper, but with coil it's really not. I'm just telling you my experience. If others can evolve their servine in time without too much hassle and pull off a coil sweep too, Skyla should definitely not be considered a bad matchup. Basically, if it's stupid but it works, it ain't stupid.
Brycen: yeah, cryogonal. Because of its speed it also gets either a leaf blade or a leech seed off against Beartic, which should make it easy for something else to finish the fight. Definitely no sweep, but Serperior can still be quite useful here.
Drayden: It can honestly duel with fraxure quite easily. Just use leech seed and spam some returns. Even haxorus can't really kill Serperior quickly. Again, no sweep but far from useless.
Shauntal: agree. It beats half her team so it's quite good here.
Grimsley: It's decent here actually. It beats both Krookodile and Liepard, so again, half the team beaten.
Caitlin: aside from Sigiliph, nothing hits Serperior super effectively so it can put its bulk to use. Leech seed takes advantage of Musharnas and Reuniclus' high HP and leaf blade can do some damage. You can't really set up anywhere (maybe Gothitelle), which is a shame, but overall this is not a straight up bad matchup at all.
Marshall: leech seed heals back a lot of HP because of Throh's high HP. This makes setup easy. It somehow never used storm throw against me, but if even if it did, I'm sure Serperior could take a couple with leech seed support. After six coils, everything just dies to leaf blade. So yeah, easy matchup.
N: you are right, the setup works best in black. In white, you have to lure in Carracosta somehow and then start the setup. Overall, I would still consider this one of Serperiors best matchups in the game, considering how strong N is otherwise.
Ghetsis: I know I got lucky here, I'm definitely not saying Serperior has a good matchup against Ghetsis because it doesn't. I just felt like mentioning it because I thought it was funny, and because it really shows just how bulky Serperior is. Overall, poor matchup.
This is the full overview of MY experience with Serperior. I hope other people can ratify its performance against things like Skyla and Marshal. Anyway, based on these results, I would say Serperior deserves B AT LEAST.
I'd like to see more testing before Audino goes to C. I don't see it on the level of Dwebble or Litwick.
Blitzle in C? Ehhh. What does this thing do in the E4 besides die? Also, its fraility is astounding.
Mienfoo is not more useful than Emolga or Bouffalant. Emolga has Acrobatics and nice Electric STAB, and doesn't wait until Unova freezes over to evolve. Bouffalant is one of the few mons actually usable in the final fights albeit late. Why use Mienfoo when literally every other Fighting is just better? D tier, no question, mostly due to literally EVERY Fighting sans Terrakion being available prior.
Yamask I can agree with, that thing is hot garbage.
About Audino, that's fair. I personally feel like it has way more upportunity to be useful than something like litwick, but this probably needs more testing. I recommend it though, it's really fun to use and it is beyond versatile.
Blitzle is already in C. You put it there yourself... I don't see it drop below that though, with how great its mid game is.
You would say emolga is useful? but.. but 75/75 offenses, ew.
In all seriousness though, Mienfoo not E tier garbage. It might come late, but it immediately becomes usefull against Brycen and team plasma. Compared to other fighting types, it might not be the best. However, the tier placement is done in a vacuum, and then it can't be denied that Mienfoo is still useful.
By the way, how come axew is an exception? it evolves at level 48 compared to Mienfoos 50, which is not a big difference, yet there is a difference of three whole tiers between them. Even durant can be in C just for doing well against the elite four, so why can't Mienshao? At the very least put Mienfoo in D, because even the unevolved Mienfoo was more useful than my cofagrigus ever was.