Haven't gone through all 11 pages of this thread but has anyone mentioned putting any device in Safe Mode to see if the battery lasts longer? I would have hoped someone would have mentioned this great troubleshooting step.
I have 245 apps on my turbo 2 (no joke) and the battery life is comparable to my old Samsung Gal S3. Keep in mind I have 245 apps installed. I am the one Tech Support tells you NOT to be. My running apps are HUGE. When I talk to others about battery life, I always say to put the phone in safe mode and test the life at that point. 90% of the time, battery life issues are app related; the rest is screen timeout/brightness, games, services such as GPS and Bluetooth, etc, live wallpaper, hardware, and cell/wifi signal issues. If the phone has a remarkably increased life in safe mode, its an app that is causing the issue. Update the apps or otherwise remove unused apps. Did I mention I have 245 apps on my phone?
Also keep in mind, any 'monitor' software is also using battery and in most all cases is running continually. Just sayin'