#1
I'm just curious how much action an electric guitar is supposed to have on the bridge or w/e (i don't know terms)

Is it supposed to be just enough so that there is no buzzing on the frets? is it personal preference? or is there a recommended amount that most people use?

thank you
Yeah, uh-huh...that's what they all say.
#2
Completely up to you.
bands/artists I've seen: Protest the Hero, LIGHTS, Andrew Bird, Flight of the Conchords, Incubus, Nine Inch Nails, Between the Buried and Me, Guthrie Govan, Cynic, The Devin Townsend Project, Scale the Summit, The Dillinger Escape Plan, Darkest Hour
#3
It's up to you, high action tends to make chords sound better and low action is more conveniant for shredding and stuff, I personally hate guitars that have action set so low you barely feel like your playing it. I'd suggest a compromise between the two, and make SURE there's no fret buzz, nothing's worst than fret buzz haha.