Sounds like good stuff. If you could ask for something more to make the team more complete though, what would you pick? I'm personally torn between Shadow Servant being the go-to hyper for a THC (so you'd get Judgement Cut, Chaotic Flame and Shadow Servant for absurd screen clearing) or Dormammu getting some Hidden Missiles like assist like say an assist version of 1C1D. (2C1D would be delicious but busted as fuck)
Haha. Well, between the two, I'd choose Dormammu getting a tracking Purification as his assist. Morrigan backed by a tracking Purification would be pretty boss. I would probably sub Vergil out for Hsien-ko and run Hsien-ko/Dormammu/Morrigan. I really do like Hsien-ko, but she can't do anything when backed by Dark Hole and Dark Harmonizer (well, except for have permanent Rimoukon, but that takes a ton of execution I don't have).
That being said, I wish the game let me pick my THC or something. Shadow Servant lets Morrigan combo into Soul Drain as a THC with
so many characters. In a way, Shadow Servant is the best THC for Morrigan, and Finishing Shower tends to be the best for others. This is because it's one of the longer hypers in the game, and lots of characters get full combos from it since they recover so much faster, and it roughly juggles your opponent around jump height. It's irregularity makes its utility risky, though.
I don't think Dormammu getting good Liberations as an assist would be a problem as long as it is handled in one of two ways:
1) There is no Liberation assist, but instead Power of the Destructor. Calling it charges Dark Spells, then he unleashes 3D0C after so many calls. As with the point version, if you happen to have 1D2C, etc., charged, he unleashes that instead.
2) Keep it as the Liberation assist, and let him keep the charges after he uses them, but give the assist a massive cooldown, around 10 seconds. This would make it a "team goal", like leveling up Frank West. 2D1C and 1D2C would probably need to fail if he gets hit though, haha.