Thanks Nivlac for the response.
I found this explanation of the PGA world ranking, I think the wonderful imaginative minds who manage and play at WGT might be able to adapt some form of variant that includes both free tournaments, ranked average, and some of the variables you name.
*Note the 25% point reduction for not playing 36 holes in a tournament, could be used for withdrawing. Decision would have to be made to take the reduction, keep the average low, or finish the tournament.
http://www.officialworldgolfranking.com/about_us/default.sps?iType=425