Devs, PLEASE STOP with the level sync already.

[Dualgunner]

So I guess the solution is to properly sync these dungeons, and make sure that the reward being given is appropriately equal

The reward needs to be as equal to the effort as possible. Either sync and reward goes up to stay relevant, or no sync and the reward stays the same. As you pointed out, Alliance Roulette has the opposite problem of 50/60: the reward is the same, but there's no sync so we have two facerolls and one not-as-much of a faceroll.