I know it might sound redundant but the more research you do, the better (IMO) experience you will have.
My bf and I will be going again this year on the 24th of the month after his first time attending last year. This will be my 3rd year attending and 4th overall party as I went to 2 in 2019.
Last year was the special Saturday
D23 party we attended and also was the first year they had the Sanderson Minnie Daisy and Clarabelle. We waited several hours in line at the beginning of the party time to meet them, but it was a priority and we had no idea if they would ever be back again so we HAD to meet them. This was even after lining up prior to 6pm in their meet line.
Even after waiting in line as long as we did we still had plenty of time for everything else. We did all the treat trails and honestly the only one that had a “wait” of sorts was Ernesto, but again that was the first year he was included and was also in a much smaller area so it was a def quickie treat trail as they were trying to get people in and out on that one because of the line. We even went through some of the treat trails multiple times!
We caught one of the parades as it passed the main hub and didn’t have to fight anyone for a spot lol.
We even had time to have a meal at Flo’s and sit and eat.
The only thing we didn’t accomplish was Villain’s Grove, but since I knew we would return to OBB at some point, being this year lol we will make this a priority this year, along with the Sanderson again because they are FAB!! Also want to see the new villains this year.
We don’t ride rides during the party because as someone else said, you can ride those any other day, priorities should be parry exclusive things like trials and special meet and greets that aren’t normally at the park. We aren’t really a fan of GOTG so the special edition for the party is not for us either.
As far as crowds go I mean it IS Disney and you’d have to expect that there will be lots of people and lines will be long…did we also feel last year that crowds were larger than normal? Of course…but again we expect there to always be crowds and lines no matter what time of year or season, it’s Disney!
Long story short, research is your friend and you definitely will have to prioritize what’s most important to you during the party. Also avoid the things that you can do any other day at the park, it’ll give you more time for the party exclusive things.