C. Viper - Cause she’s top tier, and has top tier looks, with a solid theme, what’s not to like? (besides that salty people that can’t deal with her unorthodox arch type)
Abel - Cause he’s pretty new to SF with IV being his first game, surprised he was in SFxT though. Abel is one of the few grappler’s in SF, might as well put him in.
Gouken - Could careless about this ass character, but for some reason i can see him sitting on the far bottom right of the SFV character select list as one of the characters that everyone will forget about now and then, kind of like how he is now, along with Dhalsim, Dan, and a few others.
Hakan- Cause he’s only in SFIV, and pretty sure they’re going to let him get in on the action another time around.
Characters that are not:
Oni - Basically an Evil Evil Akuma, he was originally just a way for Capcom to save money without having to make a character from scratch during the AE days, similar to what they did in USF4. I honestly don’t think anyone would care (besides Oni mains, but who cares) <- That part was rhetorical
El Fuerte - Just look at his move set, totally R. Mika inspired, he can easily be replaced by the real thing. Mika is also good eye candy, especially when she gets her shot at next gen boobies :3 (fan service) Finally, most people hate El Fuerte anyways, the world would hardly notice.
Seth - Self explanatory.
Rufus - Consecutively scores low on popularity polls, even lower than the other 3 (besides El Fuerte) horrible design, and so much more. Unlike the rest, i can see them worming Rufus into SFV in future DLC though.