I get it from an aesthetic standpoint, for sure. As far as separate parts, just remember that you will have to have a module for each instrument you wish to amplify coming into the effect rack (or one module with many inputs), hi-z inputs for the guitar (and outputs), a mixer type module or two for sending aux signals and mixing the returns. Its a lot of stuff.
I built a small mixer that I originally intended to use with guitar, pedals, an OP-1, or whatever I had around. It uses a Hendrikson, a Quattro Figaro, and an ABC Mixer - all Bastl. It has a nice wooden aesthetic that I like and I found/fitted a small wooden box to house them. It works well. The Quattro Figaro is well equipped with normalled inputs to do a lot of what you want.