Wi-Fi Battery Drain Issue Solved (at least for me)
I thought I would post my findings on here to help people out
Back in the day when the Nexus 5 was on 4.4 there was a bug in Wi-Fi settings related to optimizing wifi. What I noticed was that in BBS I had very very high Kernel Wakelocks for wlan_rx_wake. It was the highest wakelock so I decided to download Network Log which would tell me where the data is coming from. It turns out that my phone was listening for pings from all over my network, it did not matter where it was from.
I saw that Franco had updated his kernel with wifi patches and after flashing it my issues were solved. I noticed that as soon as I unchecked optimize wifi the issue came back so I had to leave that checked.
in 4.4.1 this bug was solved but you need to keep this option checked. If I uncheck it I get crazy Android OS and Wi-Fi battery drain, after checking this the issue is solved.
So in the long run, check BBS and if you see high wlan_rx_wake use Network Log to determine what is preventing your device from deep sleep. Hope that helps.