That's a Samsung issue that needs to be rectified in Android N. Can't be taking adopted storage out again. My cousin doesn't want Samsung devices after the Note 3 he has doesn't offer smart lock on lollipop. He is going with pure android this time by. I want a Samsung device as my next phone since I have the VR set, enjoy their UI, and enjoy their hardware advantages.
I would accept adoptable storage. I think 95% of what I use will not suffer from it and/or will not be noticeable. I never take my SD card out nowadays.