Parker is the only real PG on the team. Hill has the ballhandling but not the playmaking. Manu has the playmaking but not the ballhandling. TP is the best ballhandler on the team (and in the league) and, when healthy, creates more plays than anyone on the team. Ginobili is easily the craftier and skilled playmaker but in terms of quan y and consistency it's no contest.
That said, if Parker is healthy enough to drive down the lane, that takes away almost all of his playmaking ability. He's great at using his drive to create space for other players. But he's not someone who can pick you apart with passes from the perimeter with the defense sagging.