Help me level up my game? Teach me how to MSS?

So, I play some SSF4 (Im aight, 2 B-ranked characters) and I tried picking up MvC3 right when it came out. I enjoyed it for a while, but Im just total garbage. Got bodied every time I played except for the occasional gimmick win or something.

Im thinking about picking it back up and really trying to learn the fundamentals and play well. I figure Magneto, Storm, Sentinel is a good, tried-and-true team to learn on, that isnt going to be rendered irrelevant (phoenix teams) and is fairly standard, play-wise (as opposed to she-hulk and spencer or something). Although, I am open to suggestions for other teams that are viable for this purpose.

Can someone with some experience and a mic on XBL play with me in the upcoming future? talk me through what Im doing wrong and such. Or you could just kick my ass, it will still help. My XBL name is Regal Stirling.
Also can you point me toward the most effective tutorial videos, threads, articles, etc.? For the game in general or for MSS.
Or just any advice you have. common newb mistakes you wanna warn me about, proper MSS assist choices, etc.

If there was thread for this kind of post already, sorry.
Thanks in advance for your help SRK!