I played Darkstalkers 1 & 3, and I love both. But the stories behind the characters leave me blank. I think the next Darkstalkers game should have a very well-done story system, not just the same pattern of: kill every other character, then something happens.
also, they should have alternate costumes, like playing as Jon Talbain in human form. ah, and animated cutscenes instead of slide shows.