And in your trade scenario, the Jazz are getting??? Role players and an expiring? All at the expense of another prospect and draft pick? Or, in other terms, the Jazz give up interior scoring for outside shooting. A wash. Anderson and Millsap are redundant, and can't play together, thus their perceived combined strength is negated.
Jefferson has more value than when the Jazz traded for him (essentially two first round picks). Shorter contract, no injury issue as opposed to long contract, ACL injury.
It would be better just to let Jefferson's contract expire next season (there's the cap relief) and retain our young players and the GSW pick, which should turn into a starting SF. That's better value than Brooks, Humphries, etc.
Why are you so caught up in playing Anderson and Millsap together?? Anderson would not be the starter. Favors would be the starter along with Millsap. You could bring Anderson off the bench to play alongside Favors or Kanter or millsap. They are better defensively because the two best defensive bigs we have play MORE(ie Favors and Kanter) We could play Millsap and Anderson at time when opposing teams go small and Anderson guards the opposing teams "center" with Millsap guarding the four spot. This would be an occasional combination but not the starting front court.
The problem, then, is that you're trading Jefferson for backups and trading prospect for prospect, while also trading a likely lotto pick. That's neither good for the present, nor good for the future.