I'd probably "canon-weld" Darkstalkers into DMC.
Its probably the easiest crossover to pitch as well as it creates a whole set of opportunities to explore.
Plus if you ever wanna move beyond the Sparda family drama.....they are an easier sell because they already have a fanbase.
@Ronin
Just laying out options. New characters are hard to establish so bringing in the cast of Darkstalkers is easier.
They necessarily don't have to be replacements but plot generators. DMC is based on the case of the week formula so they bring countless new ideas for cases.
Plus your always going on about how Dante should date a demon so now you got a wide variety of options.
I'm pretty sure there could be an audience for DMC x Godhand, Viewtiful Joe, Okami, Strider Hiryu etc.
Plus it gives DMC a home outside of DMC which gives us more to talk about.