It is an awesome project! Great designs and functionality I was looking for
I am also experimenting with meshtastic (on a modified lilygo t-echo device) + ATAK and for messaging it works great. However I went a way to integrate it also with samsung phone. I was also thinking about adding additional module for 2,4/5GHz mesh networks to achieve the transfer of photos and voice and eventually be able to receive video stream from drone. Are you able to share what hardware and software you used for 5ghz mesh network (apart from mikrotik module)? (equivalent of meshtastic that will create the mesh network forwarding through hops and working with multicast in ATAK)
I'm also thinking about adding some kind of SDR device to be able to receive everything

Bidirectional SDR would be the best, but it would make the project much more difficult and expensive and I haven't found reasonably priced and high power SDR's.
Again, great achievement!