Best android version for Nexus 7 2013?

[AC Question]

Ok, so I have a Nexus 7 2013 and I love it. I want to know what version of Android is best for it. By best I mean highest performance in games, battery life, and overall smoothness. In my opinion Android 5 and 6 look prettier, but it won't bother me if the version is below and doesn't look as good. I just want performance.

 

[jasonandrews25788]

android marshmallow of course with better battery optimization