I have been going to WDW since 1971. I remember the ticket books - a lot of time was spent between rides deciding what to use those precious tickets for (not unlike the time people are spending now deciding what to use their precious FP+ for). When Epcot opened, and Disney went to an all inclusive ticket, we would get in a line if it was less than 30 minutes only - and we managed to see everything we wanted to.
As more parks opened, and more people visited, it became more about the time of year we visited. I've been going in September and January for years, as well as other less crowded times. We made the mistake of booking a three day weekend over Christmas back in the late 80's, and didn't get in a single attraction all weekend because we refused to wait in long lines (still had a good time though - really enjoyed the resort that trip).
I have never been a huge user of FP, just because I couldn't see running all over the park. Occasionally I would pull a Soarin FP, but then I'd find myself just hanging out in the Land pavilion waiting for the time to arrive. So FP wasn't a big part of my Disney day. As an AP holder who doesn't have to see every thing every trip, I would still just go by wait time, and if it was less than 30 minutes, I'd give it a go.
Now with FP+, I like that I can get that Soarin FP+ ahead of time and I don't feel like I'm backtracking or waiting around for my ride window. Since I didn't use FP much before, I think three is enough for me personally (understanding that others feel differently about that). In fact, I wish they let you book them individually with a limit of three instead of making you book three as a group, because I've ended up with FP+ I know I won't use, and no way to cancel them. Hopefully that will change in the future.
I am still not booking FP+ for every day of the trip - right now, I'm booking at around 50% - because I still like to have spontaneous days where I can sleep in and just see where the day takes me. However, due to having to celebrate Christmas with the family the weekend before the actual holiday, I decided to spend Christmas day at Epcot this year. Unlike that fateful trip in the 80's, I have three FP+ booked for the morning, a late lunch booked as a CP package, so I'll be seeing the 5pm show with a reserved seat. I feel like I will be just busy enough, without being over scheduled, with some time to enjoy the shops and holiday atmosphere between my FP+, ADR, and show. So I feel FP+ is a positive for me - even though a lot of people don't feel the same.