I actually go every year for Labor Day weekend (mostly to avoid the big parade/festival at home) and compared to other holidays it's really not bad. Most kids outside the NE have gone back to school and parents don't want to take them out so close to the start of the year. So MK tends to be light even on nonparty days. Only Epcot tends to be a little iffy but I definitely expect that dynamic to be worse this year with F&W starting. My usual strategy is to rope drop a party day at MK and then hop to Epcot in the evening, Friday nights there are busier but you tend not to get that "element" that shows up on Saturday nights at F&W, from my experience. I feel like all bets are off with that now. I have to imagine the
D23 folks are mostly going to be busy with con events (main reason I opted against going, I let my Gold membership lapse and didn't see the value in renewing just to go to this when I mainly want to be in the parks).
Maybe I will just treat it as a normal day of rope drop touring with a much longer midday break and go to the party in the evening. I attempted that one year at the Dolphin which really didn't work too well, but staying my first couple of nights at CR this time feels like it will make that easier.