Leveling roulette as a healer or tank: Sastasha (Savage) or Copperbell Mine (Savage).
Leveling roulette as a DPS: any 70+ dungeon.

Trial roulette as a healer or tank: Any ARR trials except Steps of Faith
Trial roulette as a DPS: StB or ShB trials.

Normal raid roulette as a healer: First four alexander raids
Normal raid roulette as a DPS: Eden raids

Alliance roulette as a healer: 8 out of 10 times the CT raid
Alliance roulette as a DPS: Ivalice raids, Copied or Bunker.

'scusami I want to do the higher lv stuff with my healers or tanks too