Well, they got a great cast anyway, I mean, make characters actually differ from each other instead of clones (Spidey, venom, hazmat for example, all web/toxic slingers). and a better combat system, but definitely keep the enviroments.
Add a small city, so we can climb, jump and run everywhere.
I mean, the area's were great but you couldn't really run and hide or evade.
And what's better then Spidey slinging and climbing through the alleys with a enraged Wolverine right behind him, would add more spectacle.
As my girlfriend pointed out when I was playing against a friend, she thought it was a movie we're watching.
With all the explosions, wallcrawling/running and throwing. So if they keep that concept, enchance it, they could have a killer game.
We need more 3d fighters, not just 2d action with 3d models like Street Fighter, Mortal Kombat and Soul Calibur for example (all great games tho, we just need a fresh wind,).