Riot Peak's pretty easy in this game. If you die, you don't have to go through all of the battles to go up again, you can just skip right to the top.
Even the "final" Riot Peak battle is relatively easy. The only issue is that one of the girls has pretty much a perpetual Ironstance on (not as bad as in the battle in Zhonecage, where it's almost impossible to stun her), so it can be annoying.
Tip: In Future Arc, the boss in Riot Peak is the best way to farm money. On Chaos, NG+, you earn about 130,000 Gald per one minute battle.