Just returned, I managed the plans of 12. Since I took care of booking all ILLs, VQ's, LL's, ADR's, tee times, etc, it was not all that stressful for the other 11. For me, it was MUCH more difficult than the old system.
The primary advantage to FP+ (besides being free), was I could have 3 FP's setup for each park day before leaving home, and I could select the time slots I wanted for these three. With
Genie+, it required being up between 7:00-7:30am each day to make an ILL (more $'s) and a LL. Last time I checked, 3 was more than 2. Math may have changed, but it hasn't changed that much. Take away the ability to set up in advance vs. morning of, AND to select your timeslots, and there is no way to pitch this as anything but a significant downgrade.
During the park day, the difference between the old and new is not as great. But still, when you booked your 4th FP+, you could select from available timeslots. With G+, you take what it gives you or you keep refreshing hoping for better. Hence the number of people walking around staring at their phones is greater than ever before. You can choose not to participate, but it doesn't change the behavior of the Genie Zombies around you.
We also ran into a hiccup related to the Swan. We had 3 groups making up the 12. One (us) was at the BWVs. The other two were at the Swan for part of the trip. Everything worked fine for one of the groups at the Swan. But with the 2nd group I could not book ILL's for them for the first 2 days (I could book regular LL's). Disney blamed the Swan, the Swan blamed Disney. After multiple conversations with both Disney Guest Relations and the Swan front desk, it was resolved. But again, it took 2 days and I still do not know exactly what the issue was, other than it was nothing we did. And despite me having screenshots of what I was doing at 7am, and that we had everything properly setup in the WDW app, Disney would not assist us on a day to day basis. Meaning, I showed how I booked ILL's for 8 of the 12, and that the other 4 were in our group and properly setup in the App but I could not book for them, and Disney's answer was too bad, can't help, talk to the Swan.
That said, when I booked a regular LL and it did not show in our app, I was able to go to the "Guest Experience Team" and they were able to add the LL for us. Of course, I had a screen shot of the booked LL to show them and I got the impression that if I did not have the screenshot I would have been out of luck. So be sure to take screenshots of everything you book.