On my P5 I was at 0.4 - 0.6 % / hr overnight. On the P6 it's currently 0.8 / hr. pretty steadily. I'm thinking some tweaking by Google will bring it down a bit. But overall it's not bad, imo. But know that the phone is really not asleep unless you turn it off. Take a look at the syncing in the background with Better Battery Stats
https://xdaforums.com/t/app-2-2-05-oct-v2-4-betterbatterystats.1179809/ I pretty much look at it when I wake up and notice if there is an unusual amount of activity on a particular app and then either tweak it, disable background use or delete it if it's not totally useful. My fitness tracker probably uses .2% of the overnight drain but I use it all the time so I'm pretty much stuck with that. There's a lot going on while the phone is "asleep" so maybe you can narrow it down some.