Id like to start this topic by either taking existing rides and adding or improving forces or just increasong speed or height.
To start the concept ive seen after running a search of coaters is to see prototype coasters against the next one after.
I looked at perilouse plunge against hydro first and i have to say there is a big improvement in the follow up track layout.
First they saw that a simple speedway style circuite would be better than having the lift hill cross over the track.
Second when you look at perilouse plunge the water is only at the half where the track meets the water.
To see the difference look at these links
perilouse plunge (the first)http://www.youtube.com/watch?v=_XB9BncEcjw
sorry if my spelling is bad the spell checker isn't working at the moment.
---- Post Info Added ----
If you look at thirteen i think the only way to make the drop better is to make it longer,
Or to have a 90 degree forward tilt then the drop, this would even work as a shuttle launch if the train releases quickly after the drop momentum would be wild and even better in the day light with height