Claire and Jack to be Castiel's grown kids at boltonlake. Typical modern day no magic AU so they can all have a fairly happy ending. Alex for Rowena as her child. I'd love to see Donna and Jody, too.
Sam needs a bedfellow, Dean seems to think he's into dudes, so that, too. Cain needs one too but he needs a woman.
Once upon a time muses for our Belle and Tink. Tink is also on the market for a male bedfellow.