I don’t think the pads have very much if anything to do with their speed. Yes, if many wr’s, backs, and db’s focused on track they could be elite. I wouldn’t be suprised if several NFL players could be considered elite right now.
Priest Holmes could be the fastest man in the world if he wanted to. He is 215 and still one of the fastest people in the nfl(at least tope 5). If he lost weight he would be the best in the world at sprinting. Ricky williams also shows great speed for a man his size. He is like 230.