Look, ANY system that requires intense thought and study for a single use is a bad system. The best design, whether that be architecture, tools, or line systems is the design that slips seamlessly and easily into the environment while making the experience objectively better. The fast pass system did not do this and for most people only added stress. It was a bad system. Can you take the heart of that system and make it better? Sure, but first you have to "sacrifice the child" of the old system and admit it's faults, namely that it preferred the uber user at the expense of the average user.
Great points.
Defenses to the old FP+ that start with:
"As a solo traveler"
"We go monthly"
"We go during the slow times"
"I have a cheat sheet that shows when the drop times are at each park" (I love this one and man, way to go! That is some next level FP wizardry!!)
shouldn't be looked at as the average experience.
Just like criticisms starting with:
"During our last trip over New Year's with 15 people in our party..."
For the average traveling family, it was a system that required a lot of juggling. For the family that was on their first trip in awhile (or ever), there was no way to master the ins and outs by the end of the trip. If you had 4-6 people in your family and you had FP scheduled at a certain park, you went to that park. Deciding to release them all and hit up a different park and play the odds of snagging same day at a new park, wasn't the best idea. Could it be done, sure. Was it likely, during times when families usually travel, not really.
The easiest fixes:
Tier the rides
Make the FP+ anytime
Give a certain number in advance based on where you are staying and what level (yes, sorry, Deluxe should get more. Club level should get more. But, so should guests who pay insane rates for motel rooms "values" VS people who stay offsite).
Charge for extras (again tier it based on accommodations, time of year, etc)
Post the FP times so people can decide when / if they want to use their FP