Fei Wong Reed's motivation
I was thinking about what could be the "bad guy" final goal, and it was somewhat hinted that he wishes to resurrect somebody, like when Fay (formerly Yuui) asked him if he wished to bring somebody back or when Yuuko stating that he would bend all the rules needed in order to grant his wish. As has been stated severaly times in the series, once you die, you are dead (obvious, huh?), so I was thinking that the reason he scattered Sakura's feathers would be that her powers isn't just dimensional jumps:
Various characters in the series can cross different dimensions (Fay, Yuuko, Fei Wong) but the protagonist party only went once to the past as far as I recall, merging the power of Mokona with the statues of the deities and the "wish-granting-moon-castle-with-a-feather". Maybe the power of the princess is not just to cross dimensions but to travel in time. This way Fei Wong would be able to travel back in time and change the fate of his "important person".
Just a thought :-k