I was not a huge fan of MvC3 and this looks like a lot of the same honestly. I would love for Capcom to go back to hand drawn character models, I just feel like they were a lot more appealing and worked a lot better for this type of game. Another thing I am worried about is Capcom giving MvCI the Street Fighter V treatment, essentailly releasing a bare bones game with barely any content or characters; I grew bored with Street Fighter V after one evening and have had little desire to pick it back up despite additional characters being added. I'll wait until it comes out to get excited.
I can say this is not the case for most of this. They've already specified it'll release with a story mode and arcade mode, so it'll have content. While it is seemingly re-using assets from MvC3, people are saying this is so they can greatly expand the roster. Bring over most of everyone outside of the mutants and then add a whole bunch more, greating a vastly bigger roster than ever before. And from what I understand, they are returning to something that is more old school for the series, which is 2 vs 2 and bringing back the infinity stones. It's being developed in house at Capcom also, which is the first time in a number of years, rather than most of their other fighting games which were done by two other developers. I think they realized how badly they fucked up on SFV and are seemingly doing everything to try and remedy that for this soft reboot.
Not that I'll probably play the game, I've never played the series, I'm just interested from an entertainment point of view. Marvel vs Capcom is an insane and nonsensical fighting game to watch being played lol