Would anyone truly be sad if only Viola and ZWEI were carried over from V?
I can understand liking Pat's style, but that seems to be the only thing most would even be sad about.
Pyrrha seems to generally be disliked and annoying, with Pyrrha Omega being the thing most people even think is worth retaining and focusing on if she did come back.
Natsu.... needs work to salvage, and I could see them do it. But if they didn't want to bother doing it.... I would not be surprised.
Xiba was pretty reviled and his shtick got tired and annoying because he was one-dimensional with the only thing that was ever explained that.... he's hungry.... and in outside info confirmed that he's Kilik's bastard son.
Leixia.... was just kind of there simply to replace her mom but more of her "cuteness" played up than they did for Xianghua.
I won't even bother talking about Elysium, and Dampierre isn't even technically from V.
I suppose my point is more that, if they "cut the fat" and kept the things that were more original yet underdeveloped (Viola and ZWEI), but dedicated the time and effort to do so, I don't forsee too much blowback from many at all aside from Pat fans more than anyone.
Zwei was my 3rd favorite character in the game surprisingly, and he also had one of the best 2P costume in the game. Viola i don't care much, but i would definitely take her over a mimic, clone or other alpha omega beta of another character.
About the other characters:
Pyrrha: She cool, but she looks a lot like cassy, and plays a lot like sophy, and if Sophy and cassie are back, which is very likely, specially Sophy, i wouldn't like to see Pyrrah. Unless they make her different enough from the 2 sisters, but then again, as someone already stated, having too many Alexandras in the game could end up being not a super great idea for some reasons.
Natsu: If they can make her more interesting, and enough different from Taki, i'm ok with her. I mean since Taki will very likely came back, her presence in the game is important imo and she's kind of iconic in the SC universe.
Xiba: If they can make him more interesting and waaaaaaaaaaaaaaay different from Kilik, why not. But personally i'd rather have a fully new character with a never seen before staff in the game.
Leixia: I mean she just seemed like a younger Xiaghua, really doesn't have too much originality, and since Xiangh will probably back, don't think Lei should come back
And i'm definitely with patro being back, as i stated before, he's kind of an awesome and original character.
In the end basically, i want the roster to be just full of "uniqueness", so no clones, and if there would be a mimic, i'm fine with one, but just 'ONE'. Also all iconic and original characters should be in. Throwing out characters like Zasalamel, Talim and Setsuka is one of the worst game design ideas PS could have done with SCV, oh wait they actually did IT!!
So yeah let's hope SC6 roster would as its greatest.