Thank you all for the great advice. After building the first parts out of cardboard, I decided to 3D print them. Building the Case part for part works great so far. Working on the ports next.
I printed the first parts of my case and I love the result so far. I used a Clear PETG Filament and settled for this semi transparent/milky look. Next I'm working on the ports.
I used Clear PETG and tried 1mm and 2mm wall thickness. 1mm was way too flexible so I'm going for 2mm. Does anyone know a trick to get it as transparent as possible? Started with 15% infill and want to see what happens with 100% but idk if that's going to make a big difference.
Designing a Case is killing me. I don't know where to put all of this, without making it too bulky. But I think I'm getting there.