Oh, that's not a bad idea. I could do a kickstarter, sell kits or fully-assembled ones that way. It would be about $300-$400 for 3 cards and a base in this iteration and at low volumes.

Think I should do it?

This is too expensive though :( and more importantly, 3 cards is too few cards.

How low you think the cost per card can go?

edit: elsewhere you quoted $80 for the base and 3 cards so if that's your target it seems more reasonable. but 3 cards is also too little, maybe a kit with 5 cards is better