In this draft, I think there are 7 or 8 consensus top-10 players, and from there is flattens out quite a bit. I think Castle's range, realistically, could be anywhere from around 8 or 9 down to about 15 or 16. I think other guys in his range are Collier, Walter, Knecht, Filipowski, etc., and team needs will play a factor in who goes where.
I'm not as excited about Castle in the top 10 as some others because I have concerns about this shooting (volume/consistency) and his athleticism, which gives him a decent advantage at the college level, but will look pretty average in the NBA. He's probably going to be a defensive-minded 2/3 who plays off the ball and secondary playmakes. How he develops offensively will determine his upside and how many minutes he plays, but again, he's starting with fairly middling physical tools for an NBA 2 or 3 and below average shooting numbers for a 2-guard.
My philosophy on the draft in general is that it's an opportunity to acquire star-level talent on a team-friendly contract. I would prefer that the Jazz really swing for upside, even if they miss. They have enough picks in their cupboard that they can afford to whiff on two out of every three picks. However, at this stage of the rebuild, they can't really afford not to take big swings. I'm not seeing as much upside with Castle if he can't be a lead initiator. He can bully smaller guards, but he's not going to beat wing defenders. If his shooting doesn't develop enough, he might not even be a starter longterm.