You might contact RS Scene Automation as I believe they make an board that controls 4 lighting loads (so you'd only need two of those) and they offer in-wall keypads with 4 sets of buttons (again, two of these). The price is right and they are very knowledgeable. The keypad is currently labeled open/close for shades, but that be able to be removed, covered, or lived with.
SW4 near bottom of page
similar to these shade motor control boards, but I think the lighting version allows for dimming
I hope this helps.