There are 3 water rides and all are kickass, that and with Kong in the middle it's way less obnoxious. A ton of disneylands rides are flat rides and it's still the best park ever. If they're highly themed, fun for what they are and add capacity, more power to the flat rides. Paraddon flyers is a mess I give you that, but the point of under 10 is no biggie, most kids rides at BG have that. Two different types of coasters means two different age groups. If you aren't big enough to go on one you can go on the other. A real problem would be if there wasn't a kiddie coaster.
I disagree, USF has barely any variety. Everything besides 3 rides is 3D and if you think IOA needs an improvement, some of USF's IPs are so outdated it's honestly sad. Different spokes for different folks I guess.
Also obviously there's more of a reason that just because. It's just an insane scale for such an IP