Yeah, I definitely think there is plenty of room for improvement. I like RCT's classic feel (and scenarios, as in the actual parks), RCT2's realism, and RCT3's expanded array of ride types and track pieces. But still, smoother curves and banks as well as more realistic graphics as well as making everything more customizable (inversions, track bankings and angles, scenery, peeps, and settings such as types of launches and car types).