Any possibility in the future of being able to sell unwanted gold cards in my deck instead to throwing them away because I have too many and can't buy the ones I really want? My character is level 47.
While I can't say whether or not that function will come to play, I wanted to remind you of another option you have for treasure cards. You can always trade treasure cards with a friend. They might have some cards that they can't use that you can or the other way around.
Just something to keep in mind for those pesky unwanted treasure cards!