i got you
bludz , just a few quick noms and i'll elaborate further if requested
A- -> B+
What is keeping Hippowdon at A-? In the current metagame, it's almost completely encompassed by Tyranitar as a sand setter and with the decline of Electric-types it's niche as a check towards them hasn't become as imperative as before, not to mention Thundurus, has adapted to it with the ubiquity of Grass Knot variants and there is an absurbly large amount of checks to it that are all extremely well in the meta. Currently, there is rarely any reason to use it over Landorus-T or Garchomp so it's spotlight has long faded.
C+ to C
ben gay brought this up a few pages back and i agree. Tyrantrum has little niche in the metagame aside from a recoiless Head Smash, but is that truly enough of a reason to consider it over Band Tyranitar or Terrakion, two similarly powerful Rock-types that bring a lot more to the table than it. Considering Dragon Dance sets, it's almost totally outdone by Mega Charizard X or even Dragonite in that aspect.
D to Unranked
Going off what I said in the above noms, Fighting-types are incredible right now, but Pangoro does not lie in that criteria. With competition such as Terrakion, Mega Medicham, and Mega Lopunny there's very little reason to even consider Pangoro with so many better options that are despite it's relatively obscure niche, simply put, so much better than it.
more controversial nom
A -> A-
Mega Gyarados is really starting to struggle to cement itself a solid place in the metagame. With Grass-types such as Physically Defensive Tangrowth and Amoonguss seeing a ton more usage and Fighting-types more prominent than ever, it doesn't really fit the criteria of an A, especially a ranking occupied by Mega Latias and Mega Medicham. Obviously when supported very well it's incredibly scary to face, but the support it requires to function as well as it'd like is what holds it back.
A few other noms I has were Thundurus-T to C+ and Conkeldurr to C, but i suppose they may be more controversial. Thundurus-T faces huge competition from Thundurus-I and with the recent decline of electric-types a drop would be fit for it and Conkeldurr fits the Pangoro argument, that there is very little reason to even use it when there are better options available.