Actually... you won't get talonflamed for that (hilarious). In fact, I'm going to throw in my support for Talonflame for S rank.Oh. 114 post. How I miss these.
Mega Venusaur would've only been A under an opportunity cost presented against it taking a Mega slot. Beyond that the discussion is finalized.
Also Aegislash to A is kind of a joke. Mixed Aegislash really ramps up the threatening aspect and isn't as one - dimensional as Swords Dance.
I'll address more later but I'm sure I will be flamed hard for this - but I can buy Talonflame in S.
Let's face it, Talon is a monster. At this point everyone knows how devastating a 180 BP Priority move is, I don't really have to go into detail. It does so much work. Completely shutting down anything weak to Flying (RIP Breloom D:) and it has great neutral coverage as well, so with CB it can revenge many sweepers/scarfers, including Greninja, Latios, and the like. Priority BB really is the ultimate "emergency button" and is an amazing late-game cleaning tool as well. Talonflame is pretty much the biggest factor behind the popularity of bulky offense (and the fall of HO).
However, there's plenty more it can do than just a simple CB set. At the beginning of the XY meta its SD set was far more common than CB, and it's still perfectly viable. It can easily run a Bulk Up set as well and set up on would-be counters like Heatran. While it's not as flexible as say, Aegislash, it really doesn't have to be. Brave Bird. Yeah. It's that good.
I don't get people saying that it requires more support than Pinsir or Charizard. Yes it requires Spin/Defog support, but how is that "more" support? If anything I'd say it requires less simply because BB means it will always be able to pick up kills (unlike the others which need to boost or outspeed their targets to be useful).
Obviously Talonflame's residual damage woes are a big hindrance, and that's the biggest stumbling block. I get that, it's awful... however, I don't mind if Talonflame dies quickly. If it did, it still did its job - it took out that boosting sweeper / revenged that scarfer / broke down the opponent's team. I know it's a tough sell, but I think it's deserving of an S-ranking.
EDIT: Aegis is still S-rank material, anything lower is just silly. Also Hippo still needs that A- rank :(