I am the OP and have a few subsequent thoughts after returning from our trip
1) park crowding is REAL. We have visited 10 times in the past 15 years and our perception is crowds have gone markedly up.
2) it really can impact how you FEEL about being there. We left during the mid-days for many days where we might not have done so prior. We just did not want to compete with the crowds.
3) planning is CRITICAL but you cannot overcome the crowds with good planning. No matter how much someone on DISBOARDS tells you you can do everything you want... that is a stretch. There is a real impact to the crowds. You will miss seeing some things or not getting as many repeats as desired.
4) you can still have a great time. We were able to obtain good FP+ prior to the trip, but missed FP+ for certain headliners. We used RD & park-close to take advantage of those. We also enjoyed some of the "lesser" attractions and realized in many ways they are not "lesser" at all. We had a great time and we were so happy to be together as a family laughing and enjoying one another company it may have been the best trip ever.
After a lot of trips we don't mind (too much) missing a few things. Even if you don't get repeat trips - don't let it get you bummed. I expect for many people traveling with friends & family the time disconnected from the rest of the world and having a great time together is really where the magic is - so absolutely enjoy it.
Will we go again this time of year? Not a chance
. But to be sure... Disney is doing its best to make sure their parks are PACKED 365 days a year and they are doing a pretty good job.