I know you will do a great job with my gift, I'll love anything I get, but here are some ideas if you need to be inspired.
Fraser/RayK: I'd love some Ms. Fraser and some Ms. Ray Kowalski. It can with be case-fic or just cross dressing for the fun of it.
Dief and Turtle: I'd love it if Dief and Turtle were buddies and had to save Fraser and Ray. A human!au where Dief and Turtle fall in love would be great too.
Frannie/Turnbull: I'd love to see RayV's reaction to his sister dating Turnbull. Some Frannie/Turnbull fluff would be great too.
Thanks for your gift. I can't wait to see what you come up with.