Thanks Lugia for taking the time to answer and your insight!! Much appreciated!! :)
I see what you're saying and although aesthetic is a part of it, it's not the only one!! ;) My project is a "Shared System" but with, as much as possible, Instruo's modules. So, 2x3U rows would be the main space and I though the 1U would be useful for the same reason as the CV Bus in Make Noise's case is.
But I guess Instruo doesn't pack as much functionality in their Modules as MN, so that's where the other options have to come to the rescue. But I see my plan was misdirected!!
If you're so kind, would you point me in the right one for this project?
Thanks in advance, mate!