maybe you can use this in the future plans (or not), since its native andriod 4.4 code what can be enabled through ADB. It enables the % battery in the status bar.
adb shell content insert --uri content://settings/system --bind name:s:status_bar_show_battery_percent --bind value:i:1
Im no 4.4 dev so I dont know if thats considered "hacky stuff", but its there. Maybe you guys might find a "clean way" to use it.