The set voltage and current (limit, whatever) and maybe the watts or some battery gauge could be in a smaller font where that white bar is in my previous post in the picture. Maybe a 5x7 font or something, let's say 12 vertical pixels. That would still leave 52 vertical pixels to put the current voltage and current .. let's say 20-22 px tall digits, leaving 8-10 pixels for borders and crap.
For watts, either show it on the top bar, or maybe have a button that when pressed, you'll see the watts on screen...
Or you could have a "white bar" at top and one at bottom and two numbers centered in the middle of the screen.