FF early because you are having a bad game?

Everyone has bad games. This does not mean it's ok to spam surrender because you lost lane when other's have absorbed your anchor plays and have a shot at winning. I've seen games where the team was actually winning and a guy just starts spamming FF. Play on.

I'd like to have setting that will autovote as long as you aren't AFK to clear the spam effortlessly.

If the whole team is tilted down and you've already transitioned into team fights, and still losing, then ok.

But it's probably not good to force your bad moment on everyone else. Sometimes you carry, sometimes you don't.

Might use that time to practice on the small things.