This is single dumbest idea to ever be thought of in the history of mankind.
Like most, I've been going to Disney once to twice a year for the past 20 years.
For someone like you I can see where this does not make sense. You go twice a year and do not feel the need to rush around and "get your money's worth". However, for some people who only get to go once every 3-5 years it is possibly a different story.
Let's take (in my opinion) a common scenario:
The Jones family hasn't been to WDW for over 4 years. Their kids are now 10 and 8. They are staying at the Poly for 10 days. The total cost of their vacation is over $10,000. Do you think they want to spend any more time than necessary waiting in lines for an attraction? While FP's in general do help, it also adds stress during the day making sure they get one for TSMM or any other popular attraction. If the Jones family can spend a little time while in the comfort of their home planning out some of their ride times....I bet they would love it. In fact, they can now let the little ones help plan out the days and be major stakeholders in the vacation (maybe a little over the top on the use of stakeholders
.
Back to the real world. During our last trip I let each one of my kids pick a day and pretty much plan it out, including which park, where to eat, what time to arrive, what time to leave, etc. My guess is they would also enjoy helping plan out the rides via FP+ too.
For the most part, we already know what park we will be in each day 6 months ahead due to the 180 day ADR timeframe. However, I can see where this can get out of hand if taken too far. As long as the FP+ return times have a decent sized return window, I am OK with picking to ride Space Mountain mid morning (10-noon) on the 13th of Sept since I will be in MK on that day.
On the other hand, I do find it frustrating having to make ADR's 6 months out and then have park hours or predicted crowd levels change on me a month out. Having only made an ADR when this happens is not a huge deal, but having an ADR AND planned out my entire day's worth of rides now adds to my frustration.