3rdworlds on 3. Feb. 2017.
I would tie it intoelites. Give some form of currency for killing bosses in
rifts, greater, and world, that you can spend to upgrade your legendaries.
But allow Regular->Ancient->Primal. But the rolls are locked. Meaning if it
is a 50% perfect rolled weapon as a regular. It would be a 50% perfect
rolled primal with the same rolls ie str, vit, +all res, crit, socket etc