For me, Blizzard Beach is probably the best water park I've ever been to. Sure I haven't gone to Schlitterbahn but I still Love BB. Summit Plummet is the best speed slide out there, and nothing beats head-first mat slides.
Not that many for me but here they are:
Steel Phantom (KW)
Python (SFA)
Psyclone (SFMM)
Viper (SFGAdv)
Hypersonic XLC (PKD)
Drachen Fire (BGE)
Python (BGA)
Hercules (DP)
Whirlwind (Knoebels)
It isn't so bad anymore but the brakes right out of the helix on the SooperDooperLooper were really bad. You go right up the hill and the brakes slam on. They're still pretty bad but nowhere near what they used to be.