I think making normal and nightmare bosses drop the essences to make a token for respecs would be a great idea. It would give new players an easier time to try new builds and give them a chance to spec out of a bad build that they can’t progress through nm or hell with. I would also suggest lowering the drop rates for the essence in normal and nm if a change like this were to happen.
I’m curious to hear other peoples thoughts on something like this. It wouldn’t be a huge game changer like a charm inventory would be, it’s more of a convenience /qol thing I think would benefit everyone.