Assuming X-Men are strictly DLC, here's 32 characters to start with:
Marvel:
1. Iron Man
2. Captain Marvel
3. Dr. Strange
4. Hulk
5. Black Widow
6. Spider-Man
7. Thor
8. Black Panther
9. Daredevil
10. Dormammu
11. Star Lord
12. Rocket Raccoon
13. Captain America
14. Ant Man
15. Loki
16. Wasp
Capcom:
1. Ryu
2. Megaman X
3. Dante
4. Vergil
5. Chun
6. Akuma
7. Necalli
8. Ammy
9. Morrigan
10. Strider
11. Phoenix Wright
12. Jill
13. Leon
14. Wesker
15. Felicia
16. Asura
Something else that is hard to predict: Are they going to hold back some of the big guns to sell as attractive DLC, or will they try to get all of the superstars on the disc, then sell the B-tier characters like Winter Soldier or Falcon as DLC? That becomes a really interesting conversation, as you can potentially leave some bigger characters off the initial roster and sell them as major draws for DLC. All depends just how sleazy they want to be with this.
Also, FAR less has happened in the Capcom realm between MVC3 and now than MVC2 and 3, which is why you see so many familiar faces.
Marvel:
1. Iron Man
2. Captain Marvel
3. Dr. Strange
4. Hulk
5. Black Widow
6. Spider-Man
7. Thor
8. Black Panther
9. Daredevil
10. Dormammu
11. Star Lord
12. Rocket Raccoon
13. Captain America
14. Ant Man
15. Loki
16. Wasp
Capcom:
1. Ryu
2. Megaman X
3. Dante
4. Vergil
5. Chun
6. Akuma
7. Necalli
8. Ammy
9. Morrigan
10. Strider
11. Phoenix Wright
12. Jill
13. Leon
14. Wesker
15. Felicia
16. Asura
Something else that is hard to predict: Are they going to hold back some of the big guns to sell as attractive DLC, or will they try to get all of the superstars on the disc, then sell the B-tier characters like Winter Soldier or Falcon as DLC? That becomes a really interesting conversation, as you can potentially leave some bigger characters off the initial roster and sell them as major draws for DLC. All depends just how sleazy they want to be with this.
Also, FAR less has happened in the Capcom realm between MVC3 and now than MVC2 and 3, which is why you see so many familiar faces.