The main others are central joystick with 1, 2 or 3 buttons either side. 2P joysticks with 1 2 or 3 buttons to the right of each stick and of course the NeoGeo setup with joystick and 4 buttons with the first button set slightly lower than the other 3.
There's also a controls project (which I can't remember the name of off the top of my head) that has been archiving control layouts for use with things like illuminated panels, CPViewer and Johnny 5 controls viewer so you might want to google about for that and give it a try.