Wouldn't it be more interesting the other way around, though? Super bar drains at a slower pace before you fire off one shot, and with each shot, the bar starts going faster. I guess the 'fantasy' here would be imitating a deadeye cowboy that takes his time to scan his surroundings before executing a spree of firey bullets to end his foes. If you know about Overwatch, the character McCree's ultimate ability is kinda what I'm talking about. Just spitballing, tho'.