Lizzie/Fitz.
I went "what is the worst possible outfit I could get William Darcy?" and IMMEDIATELY thought of Merlin. The fact that he's a Disney character just makes everything so much better. OH! You could cosplay! I'll need to find a long flowing beard for him on the cheap, though...
Just promise to mourn me enough for you and my mother at my funeral, Lizzie B. She does love a good dramatic cry.