I don't think there is much doubt that Wall has the most super-star potential of the group. He is incredibly explosive, can get anywhere he wants to on the floor, and has good point-guard skills. He's not a savant with his passing and his shooting is inconsistant, but he's going to be an upper-tier point guard.
I see a Wall and Tyreke back-court as two potential super-stars that you hope mesh together. Tyreke will best dominate at the PG position, and while you can have him at the SG position it's really going to hurt him as he is terrible playing off the ball and doesn't have the shooting necessary to compensate.
Wall is strictly a point-guard. So if you bring in Wall you have to move Tyreke over to the SG position, and I don't think that will go over very well, especially if Tyreke can't have the ball in his hands as much as he needs.
So two potential super-star talents, but I just don't think that they will be a dominating back-court.
Now you can say that we should draft Wall, see how it plays out, and if we have to trade one, then we get good value.
The problem with that is this:
If this is our last opportunity to draft elite talent, let's not waste a year or two in a 'wait-and-see' mentality, only to come to the conclusion that a trade needs to be made.
That is going to waste value time in developing a team identity and fostering team chemistry.
So for those reasons I would either take Evan Turner overall #1, or draft Wall, but trade for Turner.
Whereas I see Tyreke and Wall not meshing, I see Turner as star talent, and start talent that also perfectly compliments Tyreke's game. Though Wall is more explosive, Turner has better size, better skills, and his athleticism isn't that far from Walls.
As to why I'd select Turner over Wall here are a few reasons:
First of all, Turner is a great mid-range shooter. If you like how Beno can pull up and shoot that jump-shot then you'll love Turner's ability to do the same thing. Turner's shot is a bit flat and he isn't a great 3-pt shooter, but he is a great mid-range shooter.
Second, Turner is 6'7 and is a fantastic defender.
So if you pair Turner with Tyreke and then add Donte Greene, you've got elite defenders at the 1,2, & 3 spots. (Wall is also a great defender as well, but I think you get more versatility with Turner on defense)
Third, Turner is a fantastic ball handler. So he can share the ball handling duties and initiate offensive sets if needed.
Fourth, Turner is an outstanding rebounder. A Tyreke/Turner backcourt will probably be the best rebouding backcourt in the NBA.
Fifth, Turner was absolutely comfortable in letting his teammates do all the scoring as long as Ohio State stayed out of trouble. He is far better at playing off the ball than either Wall or Tyreke, and I think that he would be far more willing to play the 'Pippen' to Tyreke than Wall would. I just think there is a far less likely chance of a clash of egos if you pair Turner with Tyreke compared to Wall.
So Turner brings the Kings a SG who has great size and length, defense, ball-handling, rebounding, and mid-range shooting who will most likely let Tyreke run the show at point guard. Though Wall may be a better talent, I don't see him bring as much to the Kings table as Turner.
I honestly think that a Tyreke/Turner back-court would be the best in the league mid-way through next year.
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I mentioned that I don't think that a Tyreke/Wall pairing will work. So if Turner was off the board, I'd consider picking Wall and then trading to get DeMarcus Cousins. Cousins will be a beast and I think will help this team more than Wall. But, it's one of those really hard things where you might end up regretting that sort of trade.
If I couldn't get a good deal done, I'd have to stick with Wall, but I'd definitely be shopping around for a Cousins + goodies for Wall trade.
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Finally, we desparately need a big man. So if we select Turner, it means that we need to put all our assets together to get a big man. We've got the $$$ to sign a max free-agent, and we've got young cheap talent (Hawes, JT, Landry) that we can also use to trade for a big man.
So if Turner is available, I say draft him, then use all the rest of your resources in getting the big man we need.