Tired of paying for Apple's continued failure. Give us option on phone (NOT thru itunes sync) to MANUALLY delete songs from playlists or the iphone altogether.

Question

It happens every time I make iTunes music purchases: entire playlists get wiped out, and all I can sync onto the iPhone 5 is what I just purchased, UNLESS, YET AGAIN, I completely restore it to factory and rewrite everything all over.
So sad, Apple.
Yes, I have looked thru the forum threads yet again, and found no other working solution.
Yes, I tried backing up the phone 1st but still get stuck with (expletive) I wanted off the phone, and stuff I wanted on there, ISN'T there.
For whatever (insert expletive of choice) reason, it will NOT sync my old playlists.
For whatever (expletive) reason, if I check "manually manage music" under the Summary tab, then go over the music tab, something (expletive of choice)  up in the software decides to uncheck the "Manually manage music" box under the Summary tab, and it just creates a zero-progress loop where I can't sync the old playlists, or even new ones I create, onto the iphone.
Worse, songs I tried to take off of it long ago seem to manifest the (expletive) right back onto the iphone out of nowhere, and unless I completely restore, LIKE I'M DOING AGAIN, there is no working option I have found that removes the song(s) I THOUGHT I GOT RID OF.
PLEASE, Apple, is it asking too much to create a music sync that WORKS CORRECTLY all the time?
It is ONLY ever the music that does this.
App syncing, photo syncing, all of that functions properly each and every time.
And yet, oh look, it won't accept any playlists off my AUTHORIZED computer.
GIVE US THE SIMPLE option on the next iPhone update so we can manually remove/delete unwanted songs from playlists on the iphone, or from the iphone altogether, WITHOUT needing to connect it to a computer thru a faulty iTunes software that obviously consistently fails to properly sync the correct music on and take off what we don't want.
This is the final time I'm making the mistake of iTunes Store purchases until a sensible fix is implemented that addresses this fail sync issue.
Again, WHY is it ONLY and only ever the music syncing that (expletive of choice to get the point across) fails, yet apps and photos and mail & phone contacts sync correctly every time?
Yes, I read in the forum threads and customer support responses what needs to be checked and/or unchecked, yet all too often some software fail decides to revert those selections right back to where they were if I click another tab and come back to it (no, it's not an administrator thing, I am the only authorized user on the computers in question).
  I'm tired of the hassle of having to redo my music library all over again, restore the phone, and hope that once more it will have the correct songs I told it to sync and NOT have a bunch of crap I never checked for it to have on there in the first place.
FIX THIS PLEASE.

Answer 1

You're welcome.
tt2