I think 3 categories (guards/wings/bigs) works best.
When you doubt between guard/wing, put him as a wing if you could see this player defending (smaller) SF's in the NBA.
If you have a wing/big, put him as a big if you can envision him playing time as a center in the NBA.
I'm going to put a list here, when I have some more time. It will obviously be a great list, because last year I had Bol, Little, Fernando, Windler, Brazdeikis, Bitadze, Gafford and Bazley a lot higher on my mock than they were drafted and look how great they're all doing
On the other hand I was much lower on Hachimura, Hayes, Poole, Langford (
), Reddish, Washington, White and Doumbouya than their actual draft positions, while a couple of them look quite good now.