UWB is really impressive and I see you have a optical flow positioning add-on board as well. Would like to play around with the current state-of-the-art, curious is fetting things to position indoors got easyer in the last 4 years, since last time I played with it.
Something I was thinking recently is using a lighthouse positioning system from Valve for indoor positioning. They have permissive licensing terms and the tech looks very promising: