I have continued to work on this. I made a video to show how it moves (sorry for the shaky footage!)
It has been substantially upgraded and is now a smooth and quite stable and easy to use mount.
My next set of changes will significantly lighten the telescope end and feature a new type of mounting for holding the scope and binoculars. I will also be drilling a lot of holes in it to further lighten that end, because every kg I shave off the telescope end translates to about 1.5 kg I can save in counterweighting.
https://www.youtube.com/watch?v=02QDfB_MBGE