radiant quests allowing you to reassign a perk point... could be helpful for those perks you regret spending that would work better somewhere else. and of course you would have to earn it, so it wouldn't be abused. maybe some religious quest? since the perks are associated with the divines i think

Not a single perk has been associated with the Divines in any way. The stars that represent the perks can be associated with Oblivion in general, because stars are tears between Nirn and Oblivion.

With that out of the way, I want to voice how much I dislike this trend with radiant quests. I said not 5 minutes ago that they make everything more fragile and about as deep as Mike Tyson.
Perk reassignment has been done to death as well. If you want a safe way to test how perks work, don't spend them until you are ready, and even then, back the game up with a save prior to spending them.

Please use the existing DLC discussion topic: http://www.gamesas.com/topic/1364960-unofficial-dlc-discussion-possible-spoilers-thread-5/