I guess the obvious ones I left out would be unchecking all the apps that send your watch notifications on the notification section. I just have the important ones such as email, text etc as I don't need to be updated on everything it just becomes a distraction. Also I go to recent apps every now and then and close all open apps.
Top tip for charging it. Turn it off completely and then charge it will do it
twice as fast or more (total guess but it makes a huge huge difference).
I also have a screen timeout of 30 seconds though it used to be 15 which is a tad too low. I don't do any of the clicky, ticky or vibratey sounds/effects on just cause I hate that stuff. Also don't have touch sensitivity on as I've not noticed a difference.
I could probably get it over what it's quoting now which is 2 days 3 hours but personally I want remote connection on, I want auto back up on, I want continuous HR and Stress monitoring, GPS and wireless networks as my location setting so it can get the best accuracy.