Dee-tox, I wouldn't call that a "true" best and worst list, almost simply because it's a nigh on impossible thing to do.
Petterd is a better player than Bell, Dunn and Newton IMO, but he would fall lower because of his injuries. Doesn't mean he's not a better player.
Jack Grimes may well be one of the best players on that list, but he's a second year player having played 1 game. Again, it doesn't mean he's not a better player.
The criteria and classifications really do need to be defined.
A list cannot be defined by "potential," it's a "quality" that cannot be qualified