Marvel Vs Capcom 2
Skullgirls is THE spiritual successor to this game, and far, far, far moreso than Mvc3. SG's engine is heavily based on mvc2, following similar (but tweaked) rules in regards to things like otg's, assist calls, chaining, etc. The move set design also follows much of the same "logic" of the pre mvc3 Marvel games (not counting x-cota which is radically different).
That being said, it's not a game for everyone. It's notoriously unbalanced, with the top 10 characters (don't listen to the people who say there are only 4 characters, at least ten or more are viable and show up in high level tournament play regularly) feeling like they came from an entirely different game than the rest of the cast. But if you can get into it, mvc2 is one of the most magical video games out there. It nails everything, strategy, simplicity, pacing, depth, a sense of manic movement and action, and just feels good to play at all times. As Justin Wong once put it "When I play 2 hours of Street Fighter, I just want to take a break and play something else. When I play 2 hours of Marvel 2, I just want to play more."
Vampire Savior
Fast paced, stylish air dash fighter with some of the funkiest and detailed character designs and animations around, and some of the best gameplay in the genre backing it up.
On the surface it might seem similar to Skullgirls and Marvel, but it's radically different in terms of playstyle and engine. Air movement and mobility is a bit more limited and unsafe than it is in Marvel/Skullgirls, but in some ways the games offense factor is even more brutal and out of control. Chaining and mixing up stylish block strings and ultra fast quick movements allows you to jump all over your opponent and rush them down to oblivion if they let you. Even a second of hesitation or blocking can lead to crippling mix ups in this game. It's all about offense, a lightning fast game of chess where pushing an opponent into the corner even for a second is the equivalent of a "check" and forces them to immediately take some desperate course of action if they don't want to get check-mated. The emphasis on short combos and blindingly fast defensive and offensive options means that defenseIf you like your games HOT BLOODED AS HELL than this is the one for you.
It's also a relatively well balanced game. The character roster is diverse with tons of unique and fun characters, pretty much all of which are viable for competitive play (except maybe Anakaris). While the top characters are very imposing, even the low tiers take them down regularly in tournament play.