Mail/iCloud doesn't sync properly! Help!

For the past year, my icloud has been on and off with syncing between iPhone, iPad. Mail on OSX never fails. It always stays in sync with the server (you can check this with icloud.com).

Mail in iOS is a mess! Some emails would stay as unread for no reason. I hate going into my app every morning and marking each one as read! Anyone know a fix?

I've done logging in and out of iCloud. It fixes it for a day or two, and then it's back to RANDOM syncing. It's not just me, my wife's device also.

Also Mail in iOS never gets out of sync with an exchange account. This is only with icloud.