ModularGrid Rack

I'm putting together my first rack. This is more aspirational road map than exact blue print. I have plenty more modules I would like to add but have left some space for the feedback I get here. I could buy all at once but I suspect starting in the top left and working my way across a few modules at a time to learn is more realistic.

I would like this to be a stand alone box as much as possible.

Thank you for your feedback. I hope my first attempt isn't too painful for the seasoned pro's.
-Garymon