It seems like there are two major complaints and one other complaint that is a notch lower.
1) Tiering at Epcot, AK and DHS
2) Limiting FP+ to only 3 per day
and to a less extent
3) Needing to plan anywhere from 1-60 days before you go
The first two are easily rectified by Disney using their existing system if they discover that those limits aren't needed based on the flow. I'm sure Disney will monitor the wait times of the FP+ queues and if they are too fast they will allow more people to get into those lines. If FP+ queues are very long then it means that there is a capacity issue and people are really complaining that more people are using FP+ as compared to FP- which to Disney is a positive.
My guess is that eventually Disney will allow a floating number of FP+ moving forward where you could perhaps only book 3 in advance but at the park based on minimal queues in certain FP+ rides allow you to book more FP through the kiosks and app. So if I'm in a standby line for SM and check my app about what to do next and see an available FP+ for Dumbo I can grab it. This might allow me get to more than 3 for the day and maybe up to 6 or 7 like before.
I guess my main point is that there is no reason that FP+ can't do the same things as FP- but it is better b/c you can use bands and an app where before you had to pull paper. The issues right now is that they are still figuring it all out. Sure it will end up slightly different since more people will have access but while Superusers will be frustrated most users will end up better off. So people are very upset b/c they think the current workings of FP+ (which aren't perfect) are how they will be for the next 10 years.
So instead of sending your complain to Disney about how FP+ ruined your trip and you'll never go back, instead explain the things you liked about FP+ (the bands, ability to see things on the app) and how if they can streamline that with allowing you the ability to find low wait lines and grab a few more FP how that would be awesome.
Disclaimer - My first trip to Disney using FP+ is in April so I haven't experienced it yet but I will go into it with a positive attitude but certainly understand there will be issues and hopefully in the upcoming months and years Disney will figure out the way to make the experience the best for everybody.
1) Tiering at Epcot, AK and DHS
2) Limiting FP+ to only 3 per day
and to a less extent
3) Needing to plan anywhere from 1-60 days before you go
The first two are easily rectified by Disney using their existing system if they discover that those limits aren't needed based on the flow. I'm sure Disney will monitor the wait times of the FP+ queues and if they are too fast they will allow more people to get into those lines. If FP+ queues are very long then it means that there is a capacity issue and people are really complaining that more people are using FP+ as compared to FP- which to Disney is a positive.
My guess is that eventually Disney will allow a floating number of FP+ moving forward where you could perhaps only book 3 in advance but at the park based on minimal queues in certain FP+ rides allow you to book more FP through the kiosks and app. So if I'm in a standby line for SM and check my app about what to do next and see an available FP+ for Dumbo I can grab it. This might allow me get to more than 3 for the day and maybe up to 6 or 7 like before.
I guess my main point is that there is no reason that FP+ can't do the same things as FP- but it is better b/c you can use bands and an app where before you had to pull paper. The issues right now is that they are still figuring it all out. Sure it will end up slightly different since more people will have access but while Superusers will be frustrated most users will end up better off. So people are very upset b/c they think the current workings of FP+ (which aren't perfect) are how they will be for the next 10 years.
So instead of sending your complain to Disney about how FP+ ruined your trip and you'll never go back, instead explain the things you liked about FP+ (the bands, ability to see things on the app) and how if they can streamline that with allowing you the ability to find low wait lines and grab a few more FP how that would be awesome.
Disclaimer - My first trip to Disney using FP+ is in April so I haven't experienced it yet but I will go into it with a positive attitude but certainly understand there will be issues and hopefully in the upcoming months and years Disney will figure out the way to make the experience the best for everybody.

. We booked our FP+ last night, 5 people. We used the web site on my iPad since the apps were buggy; my friend couldn't even copy her FP to her DD, she had to sign in on my iPad for the web site. The app still is not displaying properly, so I am just saving images of the screen on the web site. Even so, there are times when I try to pull up the FP even on the web site and it instructs me to call IT. I can see it on some sections but not others
. It is not a very well constructed web site or app.
.
.