I get the sense you guys are wanting to answer the most athletic as in the best player that was really athletic. If you are just talking athlete, pure athlete, at the PG spot in every aspect of what defines a great athlete, meaning strength, speed, agility, then I don't understand why everyone is not answering it Ron Curry, as I have.
Curry was an amazing athlete, between his getting hurt and some friction between the basketball head coach and the football head coach at the time, we really never really got to see the best of Ronald Curry on the basketball court. Had he just played basketball for us and nothing else, IMO he would be cashing NBA paychecks now days.