Modular notebook desktop shelves (parametric)

The designThe target audience for this system is, ultimately, me. I figure there has to be more people out there who have similar taste, which is why I have made the system customisable using CAD parameters. As a professional academic in the humanities, I read a lot, take a lot of notes, and am in constant need to reference my notes. This system is intended to be as easy as possible to work with, meaningI need to be able to get an overview of which notebooks are where.It needs to feel satisfying to retrieve and deposit notebooks into the system, or at least be a neutral experience. If it feels just a little bit annoying, I'm likely to just not use it and go back to whatever ad hoc mess I had before.It should be no bigger than it needs to be. I want to be able to comfortably fit it on my writing desk.Expandability. I don't want to print a huge piece of plastic that might end up being too big or too small for my needs. No additional hardware to assemble, to reduce the steps neede