Hi Adam,
Sorry for the delay! It’s cool to see folks working in areas we don’t see a lot of activity in the makerspace! Are you using Fusion 360 sheet metal tools to get those nice radii?
Your bending jig plan looks good to me but I would definitely recommend doing some test bends to get a good feel for spring back and the radius you can hit with your chosen material thickness.
Cutting is going to be a challenge without a fiber laser or other fun industrial process 
I think you’ve identified the best tool for getting those interior square corners. With the exterior cuts, guillotine and a corner rounder would be ideal but, again, you’ll have to make due. A nibbler would be a bit faster but would struggle to get crisp lines imho.
The best answer I have for you is on the marking/layout front @Federico and I built a sharpie adapter for the big cnc. It’s a really nice way to get designs onto flat materials. Any of the @CNCtechs should be able to help you out if they can spare 15min.
Fortunately there are some good responses to getting materials in the other thread, I’ll link here for the record: Where to get Metal from?
I’d love to see progress pics as you come along!