Beagle Bone Blue/ardupilot/PX4

Rather than ask on ArduPilot or PX4 sites, I wanted to get a different perspective and figured this forum might offer some.

I have two projects that I am developing a mini version of first, but with main components. The platform for testing will be the Devastator Tank frame, then scale it up.

I am using Beagle Bone Blue to keep costs lower but I am interested if anyone has created any project below with BBB without using the ArduPilot or PX4 code. Both support BBB in experimental modes. My interest is, is it worth modifying the code for what I need or simply creating new code. I built a smaller robot that used one sensor and two small motors on tracks to simply move around the house and avoid objects. I suspect that part will be easy, but for both projects I am going to need GPS or rather RPSK for tracking. As well as a ton of other sensors for sound, motion detection ect.

Just curious on the thoughts?

Project 1:  Autonomous mower, electric and will need 2-3 mapped sections for mowing and moving over walkways. Need RPKS and object avoidance as well as homing.

Project 2: Security Rover, will need to use RPSK for mapping property lines, and specific danger zones. But most of travel will be autonomous directed by sound, movement or other actions including remote control.