I have iOS 8 on four different devices, and with the GM, not one single one of them has had any of the issues you are bringing up.
Keep in mind that most apps have not been written for iOS 8 and this can cause a huge number of issues...such as the issues you are describing
I love it when a non-developer uses developer software and then comes on here and whines that his device crashes
The issues you are describing are no more common in the iOS 8 GM than they were in iOS 7.0, or iOS 6.0...
Seriously, some people just shouldn't be allowed to access developer software when they so obviously have NO idea what they are doing.