BTW, ridiculous combo, some village + KC + Villager and you can draw your whole deck and play every non-self-trashing action an infinite amount of times (play village, play KC on Villager, draw 2 new cards, return KC and villager, draw them again, return village and one other action you have in play, draw them, now you have 1 action left and 2 cards from your deck and an action from play were returned to your hand. if the village gives you some benefit -like a card or whatever- you also have that extra benefit).
Also, returning a newly played (i.e., yet to have effect) Duration card would be weird, is the next turn effect canceled? I don't think canceling effects of cards already played is safe.
So, I think the habilty should not be thronable at the very least, and worded to avoid returning cards with unresolved effects (I think these include only Duration cards so far).