Niggross
"[Grim Reaper's Sprint] : A kill in V.A.T.S. restores 20 AP immediately. A good Perk, but wholly unnecessary since he only ever used VATS for recognizance." This would be fantastic. He just headshot 11 people in a row. 'Lucky' and 'That Gun' require 17 and 19 AP in VATS respectively. Unlike the game, in the real world headshots reliably kill people instantly. Reloading in VATS doesn't cost AP, and he has a reload speed perk. He also has a headshot accuracy perk too. He could probably kill an unlimited number of people as long as he had the ammo.