Is there a way to set some items (or activators, like ore veins and ingredient plants) to respawn on a regular basis, even if the cell itself is marked as no respawn?
There's a (new) SKSE function for Plants ... but I don't know if it will do what you want? http://www.gamesas.com/topic/1404470-resetrespawnregrow-floratreesplants-in-a-noresetzone/page__p__21435777__hl__skse%20respawn%20plants__fromsearch__1#entry21435777
And not as far as I know for the Ore and other items.