Regarding the watch list, there's a small addon that circumvents UseQuestLogSpecialItem taint:
http://www.curse.com/addons/wow/questitembuttonfix
It replaces the original ObjectiveTracker buttons with SecureActionButtonTemplate with type=item and item=link from GetQuestLogSpecialItemInfo.
I added a quick fix to my NxUI.lua using this approach, the items are usable then. But it's far from a clean implementation, and I'm not sure if I can find the time during workdays.