Is talon JG a thing?

Not really ,he doesnt have hard cc for a gangs.you also need items to be usefull.Every other jungler (lee sin ,xin,udyr etc) can just counter jungle you and butt fuck you.and then you become usless piece of crap for the rest of the game.But yea you can try ,if you want to :)

No, no, no, no, no, and last but least NO.

yes in low elo its really fun but not really viable if other team is competent

and his skill cap isnt high

No.