Jungle Japes is neither gimmicky nor random. The river god passes by at a set interval, and that is the only real hazard. It provides a clear advantage to camp-minded individuals, but people unable to overcome a clear counterpick are fools at the game.
Rainbow Cruise follows this same philosophy, imho. It's a great CP for GaW, and forces approaches. it is, again, neither random nor luck based. Pictochat IS random, but none of the hazards are particularly dangerous, exception being the spikes. And superkirbymode is so easy to counter that anyone citing that as a bannable offense is an idiot.
Smashers complain so much about things that may slightly tip the favor in a certain direction, instead of forming a logical counter to said advantage. It's like MK, but on an altogether more mundane level.
EDIT: let me addend this post by saying if it WILL aid people getting here, I'd buckle under majority pressure and ban the stages. I am, at the end of the day, trying to organize a good tournament, moral dilemma aside.