I think you go this route if you see Point Book as a long term thing. Barrett is a very good shooter and would also be a good secondary facilitator next to Booker. Obviously you take Zion if you have the #1 pick, but with pick 2-3 I would probably take Barrett. Even without Point Book he would be a good pickup due to being a good prospect, but I don't know how good the fit would be otherwise.
I think you are right. Zion has to be the first pick though. I was more neutral on Zion earlier, but after watching him for a month, I must say I am blown away so far.
1. His game is electric. He will be a marketing wonder. He will put a team on the map even if the rest of the team does not play well.
2. He plays efficiently. More efficient than Reddish or Barrett.
3. He is a mismatch. His bulk, athleticism, speed, and low center of gravity will make it nearly impossible for ANY nba player to push him off of his spot. He has leverage that we have not seen in this league since Charles Barkley--he might have more leverage than Barkley.
4. His passing and defensive skills (but not consistency) make him a useful swiss army knife type of player.
5. His rebounding and rim protection would really be helpful for the Suns.
There are aspects of Zion's game that remind me of Barkley, Draymond, and also LeBron. Oh, there are lots of differences I know, but the bulk, speed, combined with explosiveness.
Also, Zion just absolutely loves to play basketball. He goes at it with a huge smile on his face and reckless abandon. His joy is a joy to watch.