Ceiling is Corey Maggette 2.0 in my opinion. Maggette with more focus on defense and an improved outside shot would be a terrific player. This projection is very optimistic, but it builds on skills that Jaylen has already demonstrated to some degree.
I don't like the Iguodala comparison. Iggy could play point. He could handle the ball, read the defense and make the right pass. Right now, Jaylen has work to do in those areas to even become average. Let's see him become adequate at it before we expect him to be great at it.
Similarly, he's not like Pippen. Pippen was a box score stuffer - great passer, rebounder, defender. Dude averaged 16/6/5/2 for his career, and that's including his decline years when he didn't look to score anymore. A swiss army knife. I don't expect that sort of rounded, overall impact from Jaylen.