There's a rather easy way to fix Alliance Roulette: Just do a check on Level while making sure iLv is a requirement to ACCESS the Roulette, similarly to why we always put a iLv requirement to enter Expert Roulette and X0 Roulette.

Crystal Tower Alliance Raid Roulette: Lv 50, min iLv 90.
Void Ark Alliance Raid Roulette: Lv 60, min iLv 235
Ivalice Alliance Raid Roulette: Lv 70, min iLv 365
Nier Alliance Raid Roulette: Lv 80, min iLv 495

Going by the iLv requires from the top of the Alliance Raids, you'd see at Lv 50 - 59 you'd have Crystal Tower with a iLv requirement of 90 to access the roulette. However, once you hit Lv 60, the Alliance Raid Roulette bumps up to i235, along with clearance requirements to access with each expansion you hit level cap on. This would prevent any issues with people just going naked to always get Labyrinth, and would allow more variety in roulettes for those who are higher level.