I think maybe that they should have a media day and have real media go and take pictures. Have actual restaurants like Ruby Tuesdays and Olive Garden. Have arcades and real shops that are as big as the stores.
On the rollercoasters you can pick the angle you want the trains drop at. Also have different styles of trains. And have pre-built stations that you can place over the station or like on RCT2 have a station cover. Like on RCT2 you can save the coaster with scenery but you can do that on RCT3. Also they should make the river rapids better because when they go down the hill the speed goes away as soon as it touches the bottom so you dont get a big splash and maybe have like fountains getting people went and stuff like that. Finally they should have double station activacations with out doing anything special to get them.