Thanks for taking the time to leave detailed feedback like this. We need as much of it as we can get.
A few of your points come down to discoverability / help. You are correct. We agree that before the app comes out of early access we have to drastically increase that. Once we understand that the core functionality is serving its intended purpose, we will turn our attention to onboarding, help and discoverability.
It's also fair to point out that pixel density in the headsets aren't really great yet. We are of the opinion that legibility will be a problem that solves itself in the near future. User frustration might force us to reconsider that opinion sooner rather than later.
Lastly, with regard to the position of UI, it is something we have worked on quite a bit and there is still plenty of room for it to get better. We have shied away from infinitely adjustable UI size and positioning and instead tried to make something that positions itself automatically. Right now, the UI positions itself based on where your head and hands are and how long we think your arms are. The implementation is pretty naive and we intend to improve it over time. This might be another area where we have to get more mechanical to decrease frustration.