This final scenario sees the Spurs shipping out Keldon Johnson plus the 9th and the 25th picks to the Rockets for the third pick. Admittedly, I’m not a fan of this proposal, but it's probably close to what Houston would ask for. After all, Johnson is the Spurs' best asset (Murray aside) and is just 22 years old, coming off a career year where he averaged 17 points and 6 assists.
That makes him a tantalizing prospect and one that Houston would ask for in a deal, but they might settle for more picks instead. If they don’t, however, then San Antonio would have to weigh whether his ceiling is higher than the player available at three. Probably not, but most didn’t expect Johnson to be as good as he has been after being selected 29th overall.
On the other hand, by dealing Johnson, the Spurs would get out of having to extend him, which could be very expensive. Moreover, they wouldn’t have to pay Smith, Banchero, or Holmgren, big money until the 2026-27 season. They’d also be able to keep the 20th pick while only having to give up the 25th pick as an additional asset.
As for Houston, Johnson could emerge as a star and someone that they can pair with Jalen Green who was the second pick in the 2021 NBA Draft. That would be big for their franchise and they would also have the ninth and 25th pick to try and add more talent to a promising young roster. The trade could ultimately work out for both teams but probably wouldn't be the Spurs' first or second choice for an offer to the Rockets.
Of the four proposals, the trade of Vassell, McDermott, the ninth pick, and the 20th pick to Houston for the third pick and Nwaba makes the most sense. Houston would essentially end up with two extra picks and a talented young player who was recently selected in the lottery just to move back a few spots in the draft.
San Antonio, on the other hand, would get a chance to draft a future star while clearing out even more cap space to possibly sign a player to the max. While it's unclear whether the Spurs will be able to trade up, they do have the necessary assets and would have a chance at a star regardless of who is available.