Totally agree.iPhone is the cash cow for Apple. It has no reason to spend much resource on the mac line other than maintaining it as an iOS app development platform. That's why OSX is becoming more like iOS.
Hope you're restricting your children to use any social sites too. FB and others are collecting much more info than Google. FB owns its users. It knows your life, your friends, your relatives, your face, where you've been, what you like and what you hate. That's really scary.
Good insight info on supporting ipads vs chromebooks. I have a friend working for a private school about 1000 students as tech support has similar experiences. I hope Apple is listening and improve upon it. Hope iOS 9 will have the multi user accounts feature.