Devs... I still think the best idea is the quest idea where at the end of the quest you get to choose 1 illusion (of which mithaniel marrr is an option...) and only that 1 illusion. It can be a hard quest... why not!?
I wouldn't want a whole lot of choices for a 1 time quest though. It might not be a bad idea using like 2 or 3 choices.