So is your position that a course like steady ed, that has ob water on a third of the holes, shouldn't be counted with stats from a course that doesn't have ob water on it?
Remember water is not OB unless labeled that way. Landing in water could be marked the same way as it is now using the Relief Area rule 806.04 which works like OB but without the penalty stroke. BTW, isn't losing a disc enough of a penalty? However, designing for minimal OB penalties doesn't mean no OB areas, just a few positioned where players will average getting a penalty every 10 rounds or so.
It seems like the course design elements required for a course to challenge a professional disc golfer is a very different thing than course design elements that challenge a professional golfer. Why should disc golf designers model their designs after ball golf? Imo, there is also no scenario a designer can make putting in disc golf comparable to pga tour greens running a 14 stimp with false fronts.
The same design elements used for disc golf design since it started, primarily trees, elevation, and distance, are sufficient to challenge players at the highest level and provide scoring separation with no penalties needed. That's been proven year after year on the elite tour. W.R. Jackson at the Champions Cup the previous two years average 0.2 penalties per player per round. Despite how it may have appeared at Northwood with the wet, windy weather, the penalty average for both MPO and FPO was only around 1 penalty stroke per player per round, close enough to be considered a traditional track but fewer penalties would reduce some flukiness even more.
We don't need to design like ball golf, just follow similar principles for each game format we develop. If one of our desired game formats is to follow the traditional golf principle where every stroke thrown counts as 1 with none counting as two strokes or more (no direct penalties), then that dictates the various design elements to be used and how they are played. How disc golf designers achieve that will look quite different from how ball golf does it but each course layout striving for that result will have a roadmap and a wide variety of tools to get there. I know it seems like doing this would be difficult on terrain with few trees, but that's why there are experienced designers to handle those challenges.
There's no problem defining a game format where several of the same non-penalty challenges are used but with penalties attached to every one of them. I'll call it the Pressure format (sounds better than penalty format) versus the Traditional format described above. For consistency throughout the round, you design for players potentially getting penalties on almost every hole in the same way a mulligan can be used on every hole in that game format.
Maybe allowing one mulligan on every hole would be a more fun format to play on a Pressure layout with lots of penalties. That would be another game format with separate stats, but players would still follow most of the baseline disc golf rules.
Here's the trade-off between Traditional and Pressure formats. The Traditional design format, when done well, does a bit better job testing skill and reducing fluky results. Scores stay tighter longer with more hot streaks interspersed within the field showcasing good play. Pressure design format literally turns up the pressure on the players resulting in more throwing errors and stroke penalties. However, as long as the penalty elements measure skill versus random bad luck, the skill to avoid penalties or to play conservatively is an additional skill to measure. This format usually costs more time and money to mark, create accurate rules and for players to understand where the lines are located. There's likely less drama with tight finishes and contenders must hope the leader(s) take big scores and fall back rather than being able to mount a rally with good play. It's a matter of taste what format is more interesting to watch. I think some viewers like the potential train wrecks and others want to watch good play with potentially tighter scoring. Regardless, the stats, especially player ratings should be done separately the same way 3 pt, 2 pt and 1 pt shooting percentages are maintained separately in basketball.
Remember the second part of the original Frisbee slogan? "Invent games", just don't intermix elements from different game scoring formats in the same layout and expect to produce performance stats that make sense from course to course.