2I is more fun, has sf-relevant backgrounds (Necro’s has elements that hint at what went into his creation, as well as the scientist from sf: the movie), and a larger top tier, Ibuki is hella fun to use and Sean is awesome.
3s is still fun, but not as much, backgrounds are lackluster and generally not as exciting (this happens in the third game in every Capcom series), small top tier: Chun and Ken. Ibuki = no more target combo into close Hashin Sho or Yoroi Idoshi…generally not as fun to use anymore, Sean sucks. Not terribly, but compared to what he was. [Mufasa’s ghost]Simba…look at yourself…you are not what you COULD be.[/Mufasa’s ghost] Elena not as vocal as before (lost her “Yah-HAH!” sound sample for the last kick of her Brave Dance), but gains the Lynx Tail, which is fun as hell. Necro’s voice is now all fucked up-sounding, like he got kicked in the balls, and that leads to the loss of a cool duet where he and Effie sing during a winpose (before they had perfect harmony, now it sounds like a woman screaming while 2 cats fuck), and Necro and Effie are now out of sych when they say “Outta my way!”. Needless changes. There’s more gameplay stuff, but I get used to stuff like that too quickly for it to be an issue. Asthetics are what stick out for me.