Looking good. Ref the paxolin thing, this kind of material is common enough with European and professional modellers, glass fibre sheet and copper clad. No invention there. Nowt wrong with it as long as you have means to cut it Believe it or not I worked for someone building small electrical panels who wouldn't use it. Each to their own. That guff about 3D printing, honestly presumably they would have shot you down for not making your own hull moulding and presumably the same people who fettle everything and make a cast from it after, but that's OK? Ignore it.
Rock on Tommy!