So, F12 from me for: Punch FFC and he'll drop the flag.
Interesting idea.. If it's not able to be done accidentally (e.g. takes 5 seconds of punching him or something), then I'd be all for that idea.
or maybe, punching ffc would pass the flag to the teammate. Ofc, that would create its own array of problems, including: asses stealing your flag when standing still and throwing it, offensive player accidently stealing the flag while holding the fire button (and the flagger is running), repetitive flag taken sound every single time flag is passed back and forth (imagine when both flagger and teammate are punching each other).
I never played a ctf game with more than the button(s) to drop/throw the flag.