I'm not using CNC; I just agree with the previous poster that there's an opportunity. (I'd note that none of your subsequent post related to the comment you made about CNC?)
replyFor my project, I believe 19mm is plenty for carcasses - just about every mass-produced kitchen uses 18/19mm chipboard frames, and they can last for decades, outside of abnormal abuse. The main reason for using the same size is easy compatibility with standard doors/fronts together with standard fitment hinges/runners, all of which I'll be purchasing. The tops will be either granite or concrete.
I don't disagree with there being an opportunity or using CNC, I only point out that pinning everything to materials suitable to widely available CNC is too limiting.
replyLike, using plywood for verticals is overkill, they don't experience any bending, while 19+19 is 48 so you might as well use glued wood board for example.