II make "shields" for microprocessor developement boards when think I'm going to use the board a lot. I made one for ProMini and Arduino UNO.
The Pro Micro has the same number of pins and is same size as a Pro Mini, but the latter comes in two types, 3.3volt and 5volt, and their programming ports are different! The ProMicro shown here has a USB port for programming so I thought it would be best if I had a new shield. The screw terminals are 3.5mm pitch, not too small and not too big.
I made a "bumper" for the board with my 3D printer using a parametric 3D designer program.