To get it all a bit more stable and prettier I soldered 1mm copper wires from most of the mounting holes in the modules and stuck them into a piece of acrylic and just bent the wires over at the bottom. It turned out not too bad in the end... ^_^

I also added the missing boost smps and a dismantled ftdi module (the red at the top left corder) and glued it down onto the acrylic securely so I can use that USB connector as the main supply input. Then I don't risk working any of the connections on the Nano loose by plugging/unplugging the USB connector on it all the time.