I don't have many visits at other times of year to compare to, but we love early November. The first weekend in November is a long weekend for our school district, and it's our only significant time off that isn't a major holiday or the in heat of summer. Weather was perfect November 3-8th last year. Crowds were much lower than Spring Break time, though I wouldn't say they were truly low. We got to enjoy Food and Wine, could still swim at the hotel, and wore shorts and t-shirts with only a late jacket in the mornings and evenings. It only rained 1 day of our 6, and the rain was nothing like the torrential downpours of summer. Our week falls during the gap between the Halloween and Christmas parties, so MK only closed early once during our trip. (Same is true for that week this year, though our trip will be shorter so MK will be open and showing HEA for all 4 of our days.) About the only downside was that park hours were shorter than they are during summer or the major holidays, with parks often opening at 9 and closing at 8 (HS and AK) or 9 (MK and Epcot) on weekdays. Weekends it might be 9 and 10 pm closings instead.
I only have last year to go on, but Christmas decorations were out in MK and HS but not at the resorts. (I don't think AK or Epcot did much Christmas decorating last year.) "Officially" the holiday season seems to start the day of the first
MVMCP, which for 2018 and 2019 was late that first week (Thurs 11/8 last year, Friday 11/8 this year). Unofficially the trees were up at the parks, the Dreamlights on the Castle were lit for the first time on our first MK day (Sun, 11/4), and on Wed, 11/7 we saw a holiday projection show on ToT and walked out to the falling "snow" at HS. I don't know if those things happen the same time every year.
