What story do you want for Marvel:Ultimate Alliance 3?

Good story.

I'd want another original story. If it was based off a comic storyline, I'd want either Infinity Gauntlet or House of M (not sure if that'd work, but I'd love it if they found a way).

One based off the Black September event, but written and executed better.

I know. It'll never happen.

an original story . its why UA was fun and why UA2 was not

Too true. The original had way more characters and gameplay variety. MUA2 sacrificed a lot of that for the "grounded" aesthetic they were going for. MUA3 would have to be another galaxy-spanning romp like MUA1.