(BBBmicro is a reduced version of BBBmini for use with PocketBeagle, using SMD components and SMD connectors).
The more compatibility BBBmicro has with the BBBmini PCB, the better. So the same ports, port numbers and pin numbers will be used whenever possible. All connectors will be of the JST GH series (https://www.digikey.com/catalog/en/partgroup/gh-series/8397) for reliability and compatibility with the ecosystem of accessories for pixhawk2 & pixracer flight controllers.
I think we need at minimum:
+5V Power input (P11 pins: 5V IN, GND),
UART for GPS (P10 pins: TX, RX, GND, 3.3V, 5V),
UART for Telemetry (P7 pins: TX, RX, GND, 3.3V, 5V),