I would definitely vote for a sanction price based on player worth and not level.
Basing it on level would mean making the sanction price for the 2 players on the same level equal even if one is worth $1B and the other $1M !!!! I find this very stupid and unfair for the player who worked hard to develop this wealth for many reasons (and one of those reasons is to make it harder for other players to sanction him!).. What I liked about this game was that there is some strategy involved but now you want to turn it into a Bang Bang game?