That's a very easy question Arc System Works. They already did a good job with Persona. It's just if they do a Marvel game it will be too hard for most people.
They're too small. I can't see them making a properly sized fighting game with a roster of 20+ characters when they're also juggling Guilty Gear Xrd and BlazBlue Whatever. Rumor has it they're also working on a new IP. Like I said, capability and capacity is necessary.
Most recently they are working on Modern Warfare Remastered.