Here's a few things I think they need:
1. Like one of the previous posters said, they need more full service restaurants. They should have never closed the one over the entrance.
2. The arcade by The Racer and the one down by The Beast are abominable. Really, they are both in need of a overhaul and new games.
3. Kings Island needs a major roller coaster, whatever type I'm not sure, but something big. KI needs to come down like a hammer and go Blam! Here's our new roller coaster.