I just don't see how you guys are running your battery down in one day. Screen time absolutely dominates battery use. All the other stuff like kernel tweaking, task killers, greenify, is little noise ripples screen use. I only get four hours of screen time if I am working on Zooper widget or something. My normal weekdays I only get maybe an hour or two...I rarely go below 50%. I have qi chargers everywhere...nightstand, bar in the kitchen, study desk, work desk. And a charger in my car. Must be a lifestyle thing. Even on a busy work day, my phone is only away from a charger maybe 10-12 hours. I just can't see running through a whole charge from the time I leave from work until I get home. Even if I need to do a dinner or something after work, its not like I am playing Bloons TD5 while I am at dinner with work colleagues. I know some people have a less interactive job and listen to music, etc., but why not just grab a qi insert or the Samsung back, a qi charger for your desk and stop worrying about battery life?
And I would not get your hopes up for much improvement. I think most casual users can get through a day pretty easily on one charge, maybe even two if they are light users and on wifi most of the time, for pretty much any mainstream phone. There is not much incentive for improvement. Mainstream tech media hardly even comment anymore on battery life.