Quite simple, add the possibility to reset the heirloom put on ONE item (still 50% penalty).
Could even broaden it to every PP investment possible (tax, discount, maybe even price/prosperity?) so you dont have to revert everything in the fief, but the less logical thing actually is the fief controls of heirlooms. If you make one tiny error, you have to assume it or you erase everything you build until then ? Feels like character creation pre-patch when if you +1'ed str/agi/wpf/skill it was there until you retired
