Fear. Of. Missing. Out.
I have it when it comes to Disney. I don't have it when it comes to anything else! I have grossly overbooked my family for our trip in two weeks and I am going to cancel some things. Honestly, reading about everyone's awesome experiences has just increased my FOMO for this trip. I need to reel it in quite a bit.
Let me just say: My first WDW trip (with my sister in 1999), we were there for 4 nights/3 full park days. There were SO many things we didn't do. But there was plenty we did do, and it was an awesome trip! I get the FOMO thing (love the acronym!), but at some point, you have to step back and breathe. Even now, doing my annual solos, every year I have things I plan to do that just don't work out. It's OK!
I'm going against the PPs and saying I always like having some TS meals - there are places I like (Via Napoli!), places I want to try, and sometimes it's nice to sit down somewhere and relax and enjoy a meal instead of always watching the clock.
My biggest advice for you: Look at your plans and be honest - What things do you and your family really WANT to do, and what things have you planned because people here have said, "You HAVE to do these!!!" Set your own honest top priorities. Try to just embrace whatever you are able to do, and don't sweat what you don't do. Most important, don't get caught in the trap of "I have to get my money's worth!" I think that pressure leads to more stress and meltdowns and dissatisfaction than anything else.
Trust me, if you miss a parade or skip a FP, you will still have plenty of fun.
Edit - I was writing while you posted your more recent post. I'm just going to say, I have never sprung for any of the "extra magic" things (tours, etc.) and I don't think I'd get so bogged down with those. I bet your family will have a great time without a lot of extras, but I'd take a look at which ones are really the most important to you. I have no problem with ADRs and FPs, but the extras mean too much scheduling to me. Just IMO.