It's not at all clear to me that your thesis is correct. One of the easiest axles to get wrapped around is mathematics. You're basing a mountain of a mathematical postulation on a foundation of "par". Par is at best a fun target to aim at, nothing more.
If your suggested system were adopted then a massive furor would immediately breakout over what the proper par is for every disc golf hole in the world. Furthermore the argument that "luck" only (or mainly) affects "bad" scores and not "good" scores is specious. When throwing through woods, if hitting a tree is "bad luck" then missing all the tree has an element of "good luck". It doesn't have any logic otherwise. One can't have ying without also taking yang.
We just saw Ricky take a 7 on Hole 2 at the Hornet's Nest. Quite frankly I didn't see much "luck" involved. As much as I like and root for Ricky he just played the hole terribly. Even if you somehow ascribe "luck" as the culprit on his initial throw, he still should have taken a four at worst.
Should guys who drive a baseball to the warning track get credit for .25 of a home run? If the center-fielder leaps above the fence to snag your drive should you get .667 of a home run? Any system will have some technical flaws and anomalies especially at the extremes but the current scoring system is just fine.