As far as building the Spurs team, I like to think of the playoff 8.
Post
PF/Stretch
Big Wing
Lil Wing
Playmaker
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Backup Post
Backup Wing
Backup Playmaker.
From those 8, we need:
Great or Elite perimeter defender
Great or Elite Post defender
Good Perimeter defender
Four (or more) players that hit 39% or higher from three
Primary Scorer
Secondary scorer
Tertiary scorer
What we have that could be rotational on a good playoff team:
Post: Wemby
PF/Stretch:
Big Wing:
Little Wing Vassell
Playmaker
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Backup big: Sochan
Backup wing:
Backup playmaker: Tre Jones
No one else is really there.
Sochan's finishing at the rim has been so bad and his 3pt shot is still just 32%.
Look at his shot chart. 55% at the rim vs league avg of 60%. Sochan could probably be the good perimeter defender, but ideally, he would be more useful offensively. Just too many blown layups, bad shots, and turnovers. TS% of 50% is awful. Sochan can grow into that starting level on a playoff team PF/Stretch guy, but he isn't there now.
Great or Elite perimeter defender
Great or Elite Post defender: Wemby
Good Perimeter defender: Maybe Sochan
Four (or more) players that hit 39% or higher from three: Devin and no one else.
Primary Scorer: Wemby
Secondary scorer
Tertiary scorer: Devin.
I don't really care who we keep or don't keep. I think Keldon is a borderline playoff rotational guy at this point. He's a great guy, but he is beyond awful defensively, he's shooting 45/34, which are both way below league average of .475/.367.
I think Tre is fine as a backup playmaker. He makes a lot of smart plays. He will always be hunted of defense, but he puts in effort. Blake Wesley could also work his way up to that level, but Wesley is an even worse shooter than Tre. I think Devin could grow into being a good perimeter defender.
We need to add:
* Big Wing
* Primary Playmaker
* Backup Big or starting Stretch/Big - depending on if everything clicks for Jeremy in the next two seasons for him to be starting level on a good team. He isn't there yet.
* Backup wing.
One of those need to be a secondary scorer.
Three of those need to be 39%+ 3pt shooters.
One of those needs to be a good to elite perimeter defender.
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In Risacher, you can get a big wing that hits the 3pt % need. MAYBE a secondary scorer (I'm thinking maybe he's a Klay Thompson type scorer) but you likely don't get the defensive stopper there. In Cody Williams, you might get the defensive stopper and 3pt shooter, but probably not a shot at the secondary scoring option.
I don't know if Reed Shepherd will be a real primary playmaker or if he will be more of a off-ball shooter.
With Topic, you might get the primary playmaker, but he doesn't have a shot. He also doesn't appear to be a great defender.
The interest in Trae is that you fill probably the two biggest needs: Primary Playmaker and Secondary Scorer. But I don't think Trae is worth more than the two picks and swap back, plus maybe one other swap and filler. After that, you need to add 3 good shooters, figure out the other bigs and big wings. If you can add Trae and Cody Williams or Risacher, you essentially need to figure out backup wing and what you will have with Sochan and the backup big or if you can find a way to upgrade there and move Sochan to backup.
Essentially, everyone other than Devin and Wemby are replacable, but we probably have Sochan's development in our plans. Tre Jones is a solid piece, but he isn't essential by any means. Anyone else on the team is completely interchangeable.