Viper as a character encapsulates the spirit of Marvel. Spammable moves, standing lows, multiple invulnerable attacks, unblockable setups, cancellable everything. As Marvel as it gets.
Low key, I'm kind of worried right now because UMvC3 had so many unique and quirkly playstyles with stuff like Viper, Ammy, MODOK, She-Hulk, Joe, etc. I just don't see the same this time around, especially because of the overlap with the UMvC3 cast and the loss of most of those quirky characters.
And, I know it's a net positive that this isn't the case anymore, but having the deficits that some characters had in MvC3 like not being able to self-OTG made for those fun moments where you could call Joe in as an assist to kick a bomb mid-combo, and by the time you combo them up and down, you'd time it
just right so that the bomb would detonate and OTG them, and that's part of what made MvC always wild and unpredictable. MvC:I's devs seem to be increase the predictability of things in this game, reiterating that nobody could follow what was going on in MvC3 from a spectator's perspective, but, like any other sport or eSport, not only is having the additional knowledge to understand what is going on always going to be the case at high levels, it's part of the charm. Like Neonep said, the fan service has been lost in the sauce.
X is interesting, and Hunter, Ant-Man, and Gamora sound like they could end up pretty unique, but at best that's not making up for all that weird stuff that's been lost.