DickDickison: l it's hopeless to try when there are those players with 50 averages always taking the top positions. It will encourage the lower tier players to keep in WGT if they feel they actually have a chance at winning something
Nonetheless, you would still have level 90+ Tour Pros and Masters on top of the leaderboard, in the Rookie division, as the leveling up playing coin rooms is not the same as leveling up the "old fashioned way" by playing ranked rounds. With these high level, low tier players, they have the advantage of having the same, or better clubs, and balls and playing from shorter tee boxes.
IMO, I do not see any way to make the showdowns "fair" as you would like them without first having some type of uniform system of moving up tiers (which I would presume is difficult to figure out a way).