Alright, now that the new rankings have been out for a few days, I'm going to do a big list of nominations.
-> A/A+
I think iron valiant is a really splashable mon that is amazing at both sweeping and checking huge threats. Just the S ranks are threatened by its stab moves, with quite a few of the A+ mons also threatened by it or coverage moves. It is an amazing check to kingambit, quad resisting sucker punch, while forcing many other top mons to tera in order to avoid being ko'd. It's a great mon that I think is in the top echelon of the tier.
-> A-/A
Deoxys of course is a really amazing mon that has a lot of sweeping potential and supporting capabilities. While others have said that it is an A+ mon, it's lack of defensive utility holds it back in my eyes from being an A+ rank mon. However, everything else from its speed tier, wide coverage and supporting moves makes it a really top tier mon.
-> A-/B+
Meowscarada has fallen off sadly, and it doesn't have the traits of a A- mon. While it can be threatening, it has competition from weavile and darkrai as a fast offensive dark type. Weavile and darkrai are both faster and while they lack u-turn, they both can boost their offenses which makes them much more threatening. They also can pick and choose their movesets a lot easier, while meow has to stick with flower trick, knock off, u-turn and triple axel in order to not be walled by common threats. It has to choose between scarf in order to outspeed relevant threats, or boots in order to not get decimated by hazards. Not having one in multiple scenarios can make it feel like dead weight, and all these things combined make it not worthy of being a A- mon in my eyes.
-> B+/A-
Corviknight is a premier walling mon in the tier, able to check a lot of top tier mons. Mons such as gambit, tusk, waterpon, moon and rilla are checked by corv, with it being able to deal decent damage to all of them with either brave bird or body press. It can also keep up momentum for the team with u-turn, making it less passive them other walling options. Finally, it has defog, which with ghold becoming less prevelant is a bigger boon to teams that want to keep hazards off. Overall, corv is a really versatile mon that can fill a lot of roles in teams.
-> B+/A-
I honestly don't think Heatran is a bad mon in this tier, in fact I think it is pretty great. Nothing in the tier (besides opposing heatran) wants to switch into magma storm. Even something like gouging, who has recovery and can threaten out heatran, doesn't like taking chip from the trapping effect. From here, heatran can do a variety of things. Top mons such as weavile, ghold, glowking and others get destroyed by heatran and removed from the game. I've personally been liking a tera blast fairy set, you remove the steel and poison types that can threaten you after tera, and then blast everything else with damage. It's a really good mon, and is severly underrated in this meta.
-> D/C
While I understand why it fell, I think quaq is still a decent mon in the tier. While it does have its struggles, it also has very high points. First of all, it's a spinner, that in itself is something for teams to consider adding it to a team. Secondly, it's also a potentially threatening sweeper. The combo of water+fighting threatens a lot of top tier mons, such as tusk, gambit, gliscor, lando-t, moon and volc. This is great for a sweeper, and aqua step means the scarfers/booster mons that might outspeed it need to be really quick in revenge killing it, otherwise it will simply outspeed them. Resisting sucker punch and ice shard is very valuable for a sweeper. Finally, it has a wide support movepool that it can use to great effect. Roost allows it to be a solid check to many mons while keeping itself healthy, upper hand can stop some priority users like rilla and especially bolt if they are at low health, encore can ruin some setup sweepers attempts and knock off can remove items while being a decent offensive tool. Now, quaq does have its flaws, but I believe it has enough positive traits to be a C rank mon.
-> UR/D
Overqwil's main niche is that of a swift swimmer that can deal with grass types. That itself is really interesting, but it also a threatening sweeper if given only one turn. While having to setup on a teamstyle that emphasises a fast pace is annoying, that one turn can be enough to clean up a game. With stabs+water, overqwil can hit most things for super effective damage. It can even run aqua jet if it wants to, freeing up a slot on barra to run ice fang for its counters. Finally, overqwil can also support its team further if its stonewalled. Destiny bond can take down a problematic mon, which can be great for a rain team and Spikes can weaken the opposing team for a barra sweep. Overall, while restricted to one playstyle, overqwil has differentiating factors to land itself in D rank.
-> UR/D
I've said this in the past, but registeel can be absolutely devestating if supported. It's a crit me not sweeper, but it's so good at its job that it outclasses most other mons that are like it. Registeel needs ghost types removed from the game, and preferably fighting resists weakened, in order to do its thing. From there, it can switch into common mons such as glowking, hatterene and rilla, and start boosting. It can boost either defensive side with either iron defense or amnesia, and once its gotten a few boosts up, it is basically immortal. It can then use tera fighting and body press to ko anything on the opposing team, even 4x resists such as glowking are heavily damaged by it. It can use rest to recover its health, and due to taking so little damage, the two rest turns are not really a problem. In fact, they are very good for it as it allows it to pp stall stuff like corv that may try to wall it. Registeel is a bit of a gimmick, it has not a lot of defensive utility, requires support to work and has to tera, but if the stars align, it can decimate teams like nothing else.