Wow, that's quite the test. I play with Luck a lot, and I see those gem events pop up the most frequently of all of the events. Hopefully a larger sample will show that I'm not delusional
You're right about both long and short games. I should have just stuck with the map size. I think moderate games benefit the most, at any rate. Enough provinces to grab the 3 events/turn consistently is the sweet spot. It would probably turn out to be a bell curve if you graphed the benefits, there's a point where luck operates at it's most efficient. Small maps you're not hitting the 3, and large maps you (should) gain many gems from many provinces making the total gain from random events a very small percentage of your total gem gain each turn, and the percentage increase from order would offer a larger gain because there's no cap on that.
The gold income from luck will also be interesting to see, although it's not related to this thread.
Good luck, hope you don't turn up insane somewhere after this