If the policy was ever instituted, I think an exception would be made for AP holders.
I don't see FP going away anytime soon. With that said, I think that if anything changes, it needs to make sure to include resort guests, DVC members (not rentals), and AP's. I think the cost of a general admission ticket should go down slightly, but also offer the option of paying for FP access like US does.
I could see FP working very well a couple ways.
1: When the park opens you can start getting FP's for the day. I don't like the 2 hour wait between FP's b/c if the return for a ride isn't until the evening, you are waiting in lines for those 2 hours with no "perk". I think that since the FP's are marked with a return time, the "blackout" time should be that return window (1 hour?). AKA, you can't have another FP for that time slot. Each ride that has FP access can only issue so many FP's for that hour, so once they are gone, they are gone just like it works now. If you go to a FP machine that is issuing a FP for a time you already have a FP for, it issues a FP for after your current FP. I could even see the "rule" of having to have a 1 hour gap between FP return times (if your FP is for 11-12, the next FP issued will be for 1-2).
2: FP issuance for resort guests, AP's and DVC members of a certain number guaranteed per day. If you go to a FP machine it reads your card and as long as you still have "guaranteed" FP on it, you are issued a FP for return to that attraction. Once those are gone, you can attempt to get FP's just like the general public with assumed wait times and the possibility that the ride you wish to go on doesn't have more FP's for that day. This way you are guaranteed to ride (lets say 4) your (4) rides of choice for that day. Once those are gone FP's are on a first come first served basis.
(Alternatively, FP's could be issued at your resort, or reserved online and printed from your computer for AP's visiting the park on a certain day. Since these would be done in advance, they could be issued for a return time, etc. and have them automatically subtracted from the number of possible FP's issued for that attraction. Again, you would be limited to a certain number of pre released FP's per person per day (we will stick with 4). Once you have chosen your 4 FP's and have a time slot, you just show up at the FP line for that attraction and voilla.)