I was at an MVC2 tournament a couple years ago at University Pinball in Philly that banned top-tier characters. This place is famous for having some of the best MVC2 players in the world.
Here are the top characters I saw winning after several hours of watching and playing:
- Iron Man: For sure. Easiest infinite combo outside of top-tier. Awesome character besides. Proton Cannon is the poor man's Hyper Beam, and quite easy to combo into.
- Doctor Doom: Of course. Awesome assist, flies, great range, overall great character.
- Spiral: My personal favorite. Spamming knives, teleport, good assist. Easy to abuse with skill.
- Psylocke: Highly abused assist, probably only decent otherwise.
- Colossus: Almost forgot about this guy. He can be a beast, and is very powerful. Great cleanup character used with his shoulder charge assist.
Some other honorable mentions:
- Silver Samurai: Apparently this guy is nasty if you know how to use him, which few people do. More of a skill character than a "top-tier", but has potential. Saw one guy who was really putting him to work.
- Cammy: I saw one guy in particular leading and cleaning up with Cammy. She has high priority in a lot of situations if you know how to use her apparently. I don't know if this would really belong on this list however, but I saw her win a lot of matches.
- Captain Commando: Solid character. Saw him in position 2 mostly.
- Tron Bonne: Valued assist character, saw a lot of her.
Juggernaut would have been on the list if the power-up glitch* wasn't banned.
Since this was a "fun" tournament, I suspect some of the choices weren't optimal, but these were the characters I saw winning the most out of about 6 machines and 50 or so hardcore MVC2 players.
* If Juggernaut Powers-up (DP+PP) and immediately tags out without attacking in any way, his Power-up damage remains permanent for the rest of the round