Quest Reset - Giving the option to restarting/redoing a quest

Since the latest patch, the quest reward for killing Kraityn on cruel increased from 4% to 6% attack speed. I killed all bandits on cruel, but now i'd like to have the 6& increased attack speed. hope, they will add an option to rechoose questrewards (especially for those quests, where the rewards had been upgraded or were changed).