I agree that Gino retires, Gasol opts in, and Lee and Dedmon opt out. Qualifying offers are extended to Mills (at least $4 Million, maybe $4.8 million) and Simmons (approximate cap space $1 Million). That puts the spurs at ~ 93.5 million in cap, and 11 players. Add a first rounder ~$1,000,000 and a minimum hold to take them to 13 players, and they have salary of ~ 95.5 million, and $8 million below the cap (expected $103M).
Mills is going to get more that 4/$40M, at least $12M per year for 4 years, and likely $14+M. The spurs will not match that for a non-starter who isn't Ginobili esque in terms of impact.
That leaves an enormous hole in the bench, and something like $12 million in cap. If they trust Simmons/Anderson/Rookie to fill the hole, then they will use the space to try to re-sign Dedmon, (who will have options, and people putting contracts in front of him at the very least at a Baynes/Boban level). He might be on the order of 4/$40M... Alternatively, if they feel the need to add a guard, Dedmon also becomes a cap casualty, and they try and fill the hole from free agency. I think that a guard will be the FO's choice.
Obviously at that salary, we will not be getting a top tier FA, likely someone with some issues. My personal target would be Tyreke Evans (Cheap due to injury and not living up to his expectations coming into the league). Re-sign simmons with partial Bird Rights ? 3/ estimated average salary ~$5.7M ? Try to resign Lee with the Biannual exception or part of the tax payers MLE.
Gasol, Lee
LMA, Bertans, Anderson
Kawhi, Simmons
Green, ?Tyreke?, Forbes
Parker, Murray
add one rookie, and possibly Vet min contracts.