I'm gonna go older school than most of you will understand, so no apologies if you haven't a clue what game I'm talking about.
Chrono Trigger - Chrono Cross was barely a sequel. Hint to developers, don't explain how the sequel ties into the original 3/4 of the way through the game. TOO LATE.
Out Of This World - No need to explain this one. If you played it, you know what I'm talking about.
Syndicate 3 - As long as the Persuadertron was still around, they couldn't screw it up that bad.
Wing Commander - I personally liked the direction they were going with Prophecy. It's a shame what happened to Origin, much like Bullfrog. I miss spaceship combat.
Vandal Hearts - I'm sorry, but give me a tactics RPG that's not overly complex like NIS and Square enjoy making. Vandal Hearts would be it.
Suikoden - Dear god, stop making prequels and move on with the world's history already!
Destruction Derby - Do NOT make another of these if you don't plan on bringing the Bowl arena back.
Max Payne - Please not based on the movie, though.
Maybe someone could make another Star Control or Master of Orion, just to show what the third iteration of each IP should have been. Such horrible depressing endings to both series.