Assume the Spurs win just enough games to wind up with a late lottery pick, which seems likely:
Brown is better than he's being given credit for (so far). But I hate to see this team take a guy who isn't much of a 3P threat. I don't think he'll ever be that.
Patrick Baldwin Jr. is also better than he's being given credit for, but he's got a better 3P stroke than Brown, and a coach for a dad. If he doesn't stick around one more year to help Sr. out, he's probably on the list.
If Jabari Walker remembers where he left his 3P stroke, he could be a good value in the late 1st or early 2nd. If the Spurs do a deal that gets them an extra pick in that range, I wouldn't mind seeing him be their second pick. But... if Walker does find that outside shot again, he's a guy I could see flaring up later in the season, and playing his way up aroun 10-12. I'm a big believer in guys who show talent AND have a father who was a player.
I could say all those same things about Caleb Houstan, except the bit about his dad. So if the Spurs are stuck in Late Lottery Limbo, or if they maneuver their way into a late 1st or early 2nd, and Walker or Houstan are there, they would both be value picks for the Spurs. I know everybody wants a franchise guy, but they aren't likely to find one that far down, even if Kawhi did fall to 15.
Hunter inson and Johnny Juzang - either or both could be there when the Spurs take their own second round pick. Both would be worthwhile as second rounders.
And if he gets overlooked - the Spurs should have a contract (at least a 2-way) ready for Mason Gillis the moment the draft is over.
I don't like to waste a lot of time with players who aren't likely to be around when the Spurs will be picking. And I always try to find value second round picks, and at least one who is likely to go undrafted. I cried for the Spurs to sign Fred VanVleet when he went undrafted, and Max Struss is doing a of a job for Miami as an undrafted player. And I still think Jordan Nwora was a great value at 45 - especially if he hadn't gotten injured in his rookie season.
Right now, I think it's at least a coin toss that Jabari Walker plays his way into the top 15, barring injury or Colorado missing the tourney, which they could well do.