My list of tweaks so far which has enabled me to easily get 16+ hours and still have 25+% left. Today it has been off charger for 8:45 minutes, had over 1 hour of talk time, used it to keep up to date on facebook, and used it during my workout to log weights and reps. I currently have 78% battery left.
Turn off Windows Hello and Hey Cortana
Turn off Glance Screen
Set all email accounts to update once per hour (I have 4 accounts)
Unlike Skype messaging and the sms messaging client
Screen auto brightness
I have lots of apps installed that do background updates: facebook, twitter, skype, instagram, messaging, email, news, tennisfreak (my own app
), ebay, groupon, package tracker, etc.....
Not seeing any more issues battery life is great.