I’m waiting for a RPi zero, which I never used but I hope it’s fast enough, and the power consumption should be much lower than the RPi B I’m currently testing.
Also, it will probably fit into a game cartridge.
What did you do for the monitor? did you leave the 2.8″ exposed or did you put a glass in front of it? I’m considering enlarging the hole for the monitor so to fit a 2.8″, and going for a laser-cut plexiglass to replace the original GB glass.