I just wish they would fix the back gesture to never take me back to the home screen, or at least give me that as an option. It's the one thing that frustrates me to hell on an almost daily basis when I'm using Android. I don't need another gesture that takes me to the home screen, and especially not one that often closes the app I was looking at altogether, meaning it needs restarting.
Seems like a problem with the apps to me. I may be wrong, but I believe the back gesture just sends a message to the app, which can do anything it wants in response. If the app decides to close itself, there's not much the OS can do about it.
I think that the predictive back gesture feature will help a lot with this. When you swipe back from the screen edge, the animation will show the screen you're going back to, making it predictable. But having the option to disable the back gesture from sending you to the home screen would be great to have. There's nothing wrong with having more options.