I like RJ on a three-year contract rather than four years. With a three-year deal, at least it'll end when Manu's contract ends. Theoretically, that could open up another window to bring in talent.
But I agree with Bruno that a good sign-and-trade is the best option. RJ for a trade exception would be fantastic. RJ for a better fitting SF would obviously be a plus.
I'm hoping the Spurs haven't promised RJ anything. If he walks, he walks. It won't be a great outcome but the poor fit on the Spurs makes him an average NBA player at best.
If I'm the Spurs, my gameplan with RJ would be to:
1) See if any team with cap space gets desperate and wants RJ in a sign-and-trade.
2) See if any team is willing to trade RJ for a SF that can shoot and/or defend.
3) See if there are any better-fitting SFs out there that are willing to sign for the LLE.
4) See if RJ will take a three-year deal.
5) Double check to see if there isn't a comparable SF willing to sign for the available money.
6) Wait for the summer league to make sure Hairston, Gee and Anderson aren't ready for big minutes in the NBA.
7) Begrudgingly offer RJ a four-year contract with the stipulation that he shoots 1,000 three-pointers a day and loses 20 pounds.