I have a good sized cart bag since I use a push cart or ride (tournaments) and reading this I realize I carry too much stuff.
Starting with balls I always have like 4 sleeves plus a dozen old ones which is stupid because, as bad as I am, I still barely lose a ball during a round....I'll lose 2-3 in scramble, but I'm conservative (and sober) during regular rounds.
I have my full rain suit, but almost never wear the pants.
I generally put the sunscreen on in the parking lot so don't really need to carry it. The bug spray is good to have though
I carry a laser, but just use my gps watch 99% of the time
I carry tons of tees. I do break a lot, but for whatever reason I just fill a pocket with enough tees to last 2 seasons.
I probably could get rid of half my clubs. The clubs I use a lot are driver, hybrid, 6i, SW, LW and putter. I probably would need an 8i or 9i in there, but that's it. I could cut all this stuff out and carry my old SM SL 3.5 bag.....I would miss the pushcart's cupholder though....for coffee.