Douglas excels when it comes to playing defense and scoring. He's not much a pg right now because he suffers from poor court vision and a lack of good ball handling. I don't see him ever becoming a legitimate starting pg because his first instincts is to shoot and he's a subpar passer. Actually, that's fine if the system calls for a scoring pg but if not then he's a good bench player.
I know he's still learning and I definitely root for him but this team is expected to load up this summer and seriously compete next season, so I don't see him being ready to run the team. Sergio is much closer to that IMO.