I've bought the idea of getting an ergo keyboard for work, but it's too expensive to buy one from where I live, so the last days I've been learning and designing my own.
I know it won't be as good as a manufactured one but I really want to see how the result will be
I think you should probably use a CAD instead of graphics software to design…
Depends on what they want. Inkscape is perfectly fine for plate design, which you can then lift using standoffs, like the Steel Tormentor.
I probably should but I'd have to learn it first and I'm going to use laser cut acrylic so any 2d design should be fine for now, maybe in the future I'll 3d print a case, if so I'll try to use fusion 360 to do it