I agree with you. ToT doesn't have a line as long as RnR and it is usually easier to use standby on ToT than on RnR. I think the new system seems to take away the "variation" in the fastpass availability between rides. As you mentioned, you could get a lot more legacy fastpasses for ToT than RnR, but now it is limited to 1 per day, so let's think about what that would mean.
If every person in the park could only get 1 fastpass a day to ToT and because it is a thrill ride that many people would skip, that would imply to me that the number of fastpasses used per day on ToT will drastically be reduced. But think about it... both the FP and the Standby lines meet at the end and go into the same ride. If there are fewer people in the fastpass line, then more people from the standby line will be let into the ride, so the net effect of fewer fastpasses on ToT should mean faster standby lines.
As I've stated before, I think the ultimate goal of FP+ is to reduce the time waiting in line even more than legacy fastpass did, but in this case, it would seem to achieve the opposite. This may be a case where they will need to tweak the system and modify the tiering. For example, possibly allowing for a second fastpass on a ride after your first is used, based on remaining availability. Rides like ToT or Dinosaur may then have extra availability in the afternoon that could be used.
This could be true, and I think rides like ToT would be good candidates for "bonus" FP.
Unless, people who used to skip are now riding the thrill ride because of the perceived loss of not using their FPs well.
That seems to be the big wild card to me.
IF ride capacity is the same (with exception of adding the mine train)
And more rides have FP (even though some definitely don't need it and will never book up)
THEN, FP+ could be virtually be the same in handling crowds. Some people would lose FPs and other would now have access. SB lines should be shorter in some areas and longer in others.
In this scenario the frustrations are glitches (that might be fixed), a shortage of premium rides (thus the rations), and limits on multiple times on same ride and not hopping (a solution could be found I guess.)
BUT- what if the attendance is the same and ride slots remain the same but a higher percentage of people in the the park start riding more rides. A very definite possibility (and probable explanation for the chaos during busier times).
THEN, FP lines are longer and Standby times are longer for all rides.
That is what I think is happening and will continue to happen. As the FP becomes more valuable, more rare, more difficult to score... people will grab their three (whether they really want them or not) and probably use a high percentage of them because they now have a high value connected to them. They are now more like entitlements with tickets. Everyone will know they get three. Only three. No more and no less. So don't waste them. And choose wisely.
With that mentality, instead of having 30,000 people using 60,000 FP at MK (which is about right space, splash, BTMRR, and Peter Pan have about 55,000 capacity. Most other rides didn't really use that many FP), now we have 60,000 people needing 180,000. Those same 55,000 top tier rides along with ETWB are going first and then the rest of the rides are absorbing the rest.
There used to be a lot of people who would show up in the evening at parks, there would be no FP for major rides, and they would simply skip the rides. Now those people are walking in with their Fastpasses. That addition to the lines alone could be significant.
Eventually it could balance out if the people who like to ride a lot of rides in a day downgrade their expectations, ride less rides, decrease the demand or percentage of those riding. That will take a few cycles through vacations - could take years.
I think that is the only wild card Disney has to play with. Decrease demand for the rides... They need a lot of people to accept less rides while at the same time getting more (different) people to lock into the fastpass system and use their three. The more diverse population using FP would be ideal for Disney, as long as a large percentage of the population doesn't bail on going to Disney in the future.
It does seem like a huge gamble and they are fighting against the math.