Hoopsvibe has written a piece that evaluates the GM's on their drafts.
I think a much larger analysis needs to go into this. For example, he gives Atlanta's Billy Knight a b+ and Danny Ferry a C+ and Donnie Nelson a C. Also, too many picks are made by one team officially, but really are coming from another and the author doesn't differentiate. (Example: Seattle not Boston took Jeff Green)
The problem is that Knight has been drafting every year in a position to make a difference to his team whereas Ferry and Nelson have been drafting in the 20's and most of those players are non-impact players.
When scouting college players you need to break them into 5 categories: Franchise Changer, All-Star, Starter, Rotation, Roster.
The last draft was one of the best we have had in a long time and I would argue that it had the following breakdown. (Note the this means 14 starters).
2- Franchise Changers
2 - All-Stars
10 - starters (which is incredibly high for a draft)
8 to 10 - rotation (again very high)
? - roster
The point is this is one of the best and deepest drafts because of all the kids that had to go to college for a year and this is how the draft projected. Therefore, if you are picking in the 20's and get a player who plays you should be getting an A. If you are drafting in the high impact zone and you get a starter or a rotation player instead of an all-star you should get a C.
Any player who is taken in the second round and becomes a rotation player should be huge bonus points.