Will FP+ work for everyone?
No, but it fills the Void that current FP cannot accommodate.
Seemingly, as per the OP, you may have a choice of the FP or FP+, but not both.
FP+ fills that Void for people who have equal information for obtaining FP, but chose to enjoy Disney is an alternative fashion.
Disney is for families of all shapes and sizes. We should not have to run to get a FP multiple hours before intending to use them. Especially, if there is an alternative to satisfy the problem.
Disney wants me to go to DisneyQuest and other empty attractions in the morning...But if my only way to ride ToyStory on a short line or obtain FP is by going to HS in the morning, then current FP clogs the queue. FP+
may smooth out this problem....I can chose to ride at 7pm....and you can chose to ride at 9am....and you can get a FP too.
All FP users win by using FP or FP+. Original FP users can go to HS to ride TS early and often (and I was not in your way); I arrived at 7pm and you were gone. I went to HS when I wanted, not because I had to in order to beat the crowds. We can say the same for Soarin', Test Track, etc.
I believe that FP+ is more egalitarian than current FP, we can all get them before arriving and we each get the same number.
I believe that FP+ will not work for everyone, but at least we are on equal footing before we arrive....and you can still use FP system if FP+ is not right for you. FP+, as we currently understand it, may well work better for people who want to simply arrive to the Parks later or want some of the alternatives like 'preferred' seating for fireworks and parades. Or you can chose to manage your FP's by using the current system.