This is my first time posting in this thread, so if I missed something, I apologize in advance, but I wanted to comment on hawlucha, as I have recently started using it, and couldn't be more impressed. I think it absolutely deserves a slot in B rank. If I read correctly:
Reserved for Pokemon that are great in the OU metagame. These Pokemon have more notable flaws than those above them that affect how they function in the tier. Their positive traits still outshine their negatives, but they require a bit more team support to bring out their full potential.
This describes hawlucha perfectly imo. He needs support to get past certain threats that can beat him basically every time, but once those are gone he can easily sweep. The biggest obstacle hawl faces is priority, especially birdspam. Talonflame and mega-pinsir can both make mincemeat out of hawl before he has the chance to do anything, and hawl is also weak to ice shard, another common priority move. However, these threats aren't all THAT hard to contain, as plenty of pokemon counter birdspam easily, such as tyranitar, mega-manectric, and rotom-W, to name a few. Plus, fighting and flying STABs are two of the most powerful in the game, and hawlucha has access to very powerful moves in each to abuse, even with his lower than average attack stat, hitting with a base 130 move is still gonna hurt, especially after a swords dance. And if hawl can get off a swords dance AND unburden boost, it's pretty much GG right there, as very little can hope to stop him at that point. Hawl is a great choice for breaking through some of the more annoying stallmons, as well, as I will often send him in to deal with gliscor or chansey, both of which often underestimate what hawl is about to unleash on them. Basically the only thing either of them can do to hawl is poison him, which he won't really care about, as he'll SD on the turn they try, then sky attack to get his unburden boost, and finish with either acrobatics or high jump kick, depending on the situation. Even the most physically defensive gliscor won't be able to survive a +2 sky attack AND acrobatics back to back, toxic healing behind a protect/sub or not.
Just to back that up: +2 252+ Atk Hawlucha Sky Attack vs. 248 HP / 252+ Def Gliscor: 244-288 (69.1 - 81.5%) -- guaranteed 2HKO after Poison Heal
and then: +2 252+ Atk Hawlucha Acrobatics (110 BP) vs. 248 HP / 252+ Def Gliscor: 193-228 (54.6 - 64.5%) -- 94.1% chance to 2HKO after Poison Heal
and there you go, a physically defensive titan overcome by a pokemon whose low attack makes people underestimate it. Irony, thy name is hawlucha. Now with that said, hawl could potentially get into trouble against a gliscor with protect AND subs, as it'll take a LONG time to break through and get the kill on him, but those aren't too common. Usually the gliscor i see run a set like protect/toxic/knock off/earthquake or something similar. And since hawl resists EQ, and knock off would only benefit it by activating unburden, gliscor's only real option is to toxic/protect stall, and it'd be dead long before that killed hawl. I've had this exact scenario play out before, and my hawl was able to kill gliscor AND 3 more pokes behind it before dying to toxic poison.
In addition to all that, hawlucha is one of the few flying types that take neutral damage from stealth rocks, and as a flying type is immune to spikes/toxic spikes/sticky web, so he doesn't fear much from entry hazards, which are one of the leading factors to consider when adding pokemon to your team.
So in summary, I think hawl has the tools necessary to justify a slot in B rank, as it can really put the hurt on a lot of the metagame, even physically bulky threats that would ordinarily be a hassle for a pokemon with low attack.