For all their talk at E3 about wanting the storyline in SFV to feel more complete and cohesive than games of the past, and pointing out the significance of the initial 16 in particular, I can't help but believe that Karin is in the core roster and the fourth "hasn't been back in a while" character. Mika's in, and as it stands right now she has no real tie to anything or anyone else that we currently know about. Karin's family, on the other hand, has been shown to run against Shadaloo at points during the Alpha series, so Karin fronting Mika into whichever tournament this is supposed to be would give Mika a more sensible reason to be here. Plus, from a gameplay standpoint, we're still lacking a proper rekka character, and Karin's counters and other such moves feel like they'd fit right in with SFV's new mechanics.
On the other hand...I also feel way less optimistic about any SF3 characters returning, at least in the initial roster, given how mum they've been about when V takes place, and lumping someone like Urien in with the group of "classic" characters just doesn't feel right to me. There'll still be some additional Illuminati presence in the game, but I'm guessing that will come from one of the completely new characters. Zen, perhaps? Really the only character I could see making it into that spot that isn't part of the SFII generation would be Juri. Maybe Abel, but as a stretch. The likes of Guile, Dhalsim, Sagat, or Akuma seem far more likely.
