I posted this idea a long time; it was before the "suggestions" forum was created.  So here it is again, where it belongs.

I would be in favor of a few more instances where superstar players are willing to resign with their current team before testing the market.  But with that, I'd like to see their salary demands increase as well.  Maybe about a 25% increase in players willing to resign, but with steeper prices.  Their new demands could be based on a number of factors; age, current overall rating, and the player's agent. 

Here's how I envision it in a simplified version of psuedo-code:

Is player willing to resign?
     If no, then "Sorry, I'm testing the market no matter what."
     If yes, then....
          Is player 29 or younger?
               If yes then...
                    Is player's agent passive?
                         If yes, then "I will resign, my demands are [initial demand] x 1.3 /** For example, a player who would have demanded $8M now demands $10.4M to stay with his current franchise **/
                    Is player's agent aggressive?
                         If yes then "I will resign, my demands are [initial demand] x 2 /** Former $8M demand is now $16M to stay **/
                    Is player's agent medium?
                         If yes then "I will resign, my demands are [initial demand] x 1.5 /** Former $8M demand is now $12M to stay **/
               If no then.... /** player is 30 or older **/
                     Is player's agent passive?
                         If yes, then "I will resign, my demands are [initial demand] x 1.1 /** Former $8M demand is now $8.8M to stay **/
                    Is player's agent aggressive?
                         If yes then "I will resign, my demands are [initial demand] x 1.8 /** Former $8M demand is now $14.4M to stay **/
                    Is player's agent medium?
                         If yes then "I will resign, my demands are [initial demand] x 1.3 /** Former $8M demand is now $10.4M to stay **/