Were your FP+ choices tiered?
I agree, that without tiering it works great for people who want to hit the parks later. I would be satisfied if I could book Soarin' and Test Track, TSMM and Rockin' Roller Coaster, all while having a leisurely morning at the hotel. The system isn't set up for that. If you want to ride all the headliners (even just once) without a long stand by wait you still need to get there for rope drop. There's not much improvement for people who don't hit rope drop unless they don't care about picking and choosing which popular rides to ride.
I would be willing to deal with the rigid aspect of FP+ if it truly meant we could have a relaxing vacation with our big rides booked. For a family who wants to do all the headliners, it just creates stress. We have to combine waking up early on vacation with being tied to plans made 60 days ago. Ick.
This gets me thinking. What if they offer a package for purchase to remove the tiers and also offer some extra FP but not unlimited. Will that be a good thing to sell?