What would I want? A movie that features the characters from the early 90s run (Wolverine, Gambit, Psylocke, Jubilee, Cyclops, Colossus, Storm, etc.) I would like to see the team aspect and characters getting their signature moment. No origin story. Let's get into the action. Still need character development. And I wouldn't want characters randomly thrown in just for cameo appearances. If it fits the scenario and that particular character, go far it.
I wouldn't want the same villain in each movie, but I'd like for the series to build towards Apocalypse (X-Men Evolution version). I was going to say Onslaught, but I'd rather see that character in a straight-to-dvd cartoon.