Some of the changes are indeed mind boggling. A decent amount of the low tier...didn't go anywhere higher. Only one that really did was Cap who can be arguably mid-high now (he was on the cusp before, just couldn't get it to come together).
Zero does seem ridiculous but remember this...he'll still die insanely quick, and he did lose a little without the Hard Knockdown Buster. He's buffed, but he's still more mixup based than anything.
My thing is, I think people are overreacting to things. People are going crazy on the Wesker Sunglasses thing...then forget what we learned a MONTH ago when SKill said that Wesker gets his glasses back on tag outs and from using Phantom Dance. Add to the fact that he won't get full combos from Rhino Charge anymore and he's weakened enough considering the health losses and the fact he was never that damaging outside of X-Factor or Lost in Nightmares combos anyway.
Add in the lack of meter building, X-Factor changes, and all these different changes and you can't think of UMvC3 the same way as the old game. Now will it hold your attention, who the hell knows, I honestly couldn't care less and I doubt Capcom does either as long as you buy their game, but shit could be a LOT worse.
Every game deserves a chance. Just don't make the HUD an actual factor into whether you care about the game or not. People are making WAY too much of a big deal about it, after a week people will stop even caring.