I get your suggestion, but the game already unlocks at a new tier. Your stated variances would just get in the way, and decrease any value / attraction.
no one was asking what you do each day or ?ing your ability to speak, just disagreeing with your points at every turn. You still think they would work fine, just accept others do not been around the block or not. Don't go assuming others spend lives here though any more than you ideas might work - how long do you think 5 or 6 9 hole RGs a day take in between stuff at work?? So maybe once again just more flawed logic from you...Cheers
EDIT: No way would I have appreciated and therefore been any more likely to but new equipment just because a course got unlocked. The beauty of the game is learning all the courses as you go, and burning balls of course revenue wise. Banging round 1 course would be boring at any stage, and would not have been for me. Unlocking that and another at a higher tier? why in the leap of faith people might toddle of to the pro shop sooner to buy clubs, and that's assuming many play all courses anyway - big assumption. Anyway like I say I disagree with your methodology, and would not have appreciated it being forced on me and don't see any need for change based on a few assumptions from just you.
No fixed rule even here, but for this lets agree new clubs are needed at master and then Legend just for this exercise away from how some may choose to enjoy themselves. They are the only real jumps whichever way you go, and the only 2 times you "need" to think about an upgrade.
I could open it up even more but there is no point as you clearly just never even started to think any of through properly.