The cap needs to be adjusted for taxes. For example $14 million in CA would be $12.88 million after state tax. So if he is deciding between $16m in Dallas and $14m in LA it is not a $2m difference it is a $3m + difference.
In general, I have said teams caps should be adjusted by state tax. So if your state rate is 0% like Texas your cap is what is stated, but if your state rate is 12.3% like CA you would adjust the cap by that amount. I mean obviously 12.3 is the top rate and not what you pay on your entire salary, so adjust based on actual tax rate.
One way you could do it is do it post contract. For example Von takes $14m to stay in LA but the Rams cover the state tax. That could be a way to level the playing field. Of course Florida has 0% tax and the Jags are paying like crazy to get players. So maybe not change the entire cap, just give teams an exception or two who live in high tax states.
