Just a suggestion when doing the battery bump, while charging battery powered on, turn off the screen. Not 100% sure but i think it made a difference on charge time. I use the power control widget(paid) for the screen brightness. I refuse to go to 20% screen brightness. I'm not going to strain to see the darn thing, I like to see what im doing. I also choose wisely on wallpaper, usually dark themed.
For the battery bump, only do it once a month, not often. Having the screen off will definitely help you charge faster, I am not sure of the exact amount of difference it makes though. Dark vs. light wallpaper should not matter because its an LCD screen (it does matter on other smartphone screen technologies though). I use Screen Brightness widget by Curvefish (free), it has settings for 0, 25, 50, 75, 100, Auto, and has a convenient slider to get a custom level if you want a different number.