I'm so jealous reading all of these "wing-it" philosophies! I really wish I could do it... I just don't know how, ha! I am too type A. But our last trip really felt so rushed and like we were just checking things off a list at some points. I had a spreadsheet with pretty much every ride, character meet and greet, show, etc that we wanted to do, in order. We did accomplish everything, and it was during level "10" crowds, so I know it was useful. But still, I felt like it was a little less "magical" then some of our previous trips.
This next trip, I am really going to try and abandon the spreadsheet!
I know its not "winging it", but if I could stay with just FP's and not plan everything else in between, I think it would be a good balance for us. Also I realized that we have been on enough trips now, that we don't need to do EVERY attraction. That's where it began to feel like checking things off a list. Our kids are getting older each trip and have different interests and just because things like Peter Pan and Small World are classics, we don't have to feel pressured to ride them every trip. We usually go for 10 days, and even with that, there just isn't time to do everything, plus relax!
So we likely will still have a plan for where to go each day, our 3 FP's and maybe a few ADR's spread out over the trip, but I won't plan rides in between. I have to get out of the mindset that a "successful" trip is one where we saw everything, but more that we just enjoyed every minute!
I think every family has to figure that out on their own.. there is no one formula that works for everyone. It just all comes down to, what is your family's priorities and how will you best enjoy your vacation!