I too am happy with the upgrade to Kit Kat. So far, I am liking the white battery icon. It is actually easier to see. I also liked the fact that I was able to customize the quick setting menu, and that it is easier to get to the quick settings menu.
Also, my battery life seems much better.
As for the Sprint Network Optimizer, it at least does not seem as annoying as the version that was on the Sprint EVO. Still, though, I think I will try to disable it.