Since I may want to take VCC, GND, Raw, and other pins from the Pro Micro to the breadboard area, what soldering strategy would you recommend to connect the Pro Micro castellated pads to the surface pads for the Pro Micro on the main PCB?
Solder the Pro Micro directly on the board, like a surface mount chip, and add jumpers as needed with a second soldering?
Solder header pins between the Pro Micro and the breadboard area, then jumper from there over to the surface mount pads?
Wrap wires around all castellated pads and solder them as short jumpers?
Thanks,
Dan