i was wondering if anyone would be interested in pre-cut, ready to assemble cabinet kits? I could offer them pre-laminated with a variety of finishes (flat-black, textured-black, or even over a dozen metals) and all necessary hardware or as unfinished. Still have to figure out the price but seems like most similar kits go for around $500 before shipping.
I know that people seem more interested in a SWars cab than in an upright, but I wanted to respond to your original question. I'd say that the answer is 'yes', there are definitely people interested in ready-to-assemble cab kits but there're already some players in that field.
If you could offer kits at a substantially lower cost, then I think you'd be good to go. Having a pre-laminated kit would certainly save people the time and effort to paint-sand-paint-sand-paint their cabs or to try and deal with doing their own laminating.
But, for the most part, I don't think BYOACers are interested in $500 cab kits. I got my cocktail cab kit for ~$225 and that included the shipping costs. It's a great kit and well worth the $225, but there's no way I would have paid $500 +s/h for it.
Come up with a cab-kit price that's in the $200 range and I think you'll have a hot item on your hands. Offer one that's $500 and you'll probably lose to the likes of
www.arcadeshop.com ($365 for an upright cab)
www.mameroom.com ($459 for an upright)