Have you seen the 'homemade' cnc router system which is made from an 8x4 board some motors and string. Can't direct you to the video but there's a few out there. There are quite a few affordable cnc kits.
The laminate is not that bad to work with from the little experience I have with it.
for the pine i thought about painting the insides and edges but probably wont now they are more rounded off.
laminated ply is harder to work with? more likely to splinter at the edges perhaps.
ideally i'd have an app and a cnc router so you just plug in the number of shoes you have lying around and it cuts the appropriate amount of holes.
some friends are coming over tomorrow night, so i will see if i can drum up a few orders from them