Not sure if this is an issue anymore BUT rides such as water rapids, have the rapids continue moving around the entrance area so that they can be entered and it speeds the queue system up. No rapids stop at entrance IRL, you normally have to make a dash for it to get on.
I am no programmer it has to be said, but here is my thought. Before the magnificent Ride Pack i would have told you that this is not possible. BUT: I had a thought: They managed to have a constantly moving system with the Chairlifts, so maybe they can retrofit the Rapids and the Flumes with that. But having said that, retrofitting existing rides is a loot of work, and they have to justify spending the time on it. Maybe a Dev or Community Manager can chime in here, but the same thought goes about omnimovers (sorry for offtopic). In my Mind they can combine the existing Technoligies to produce the Omnimover, since all the functions for it to work are basically in the Game now.
Also, there have been numerous occasions where they fixed a "mistake". Stations are more complicated than they seem by the way. I do hope though, if there is a Planet Coaster 2 that they have more types of Stations. And the possibility of having two stations, i. e. one for unloading, and another for loading Guests.