Hi Tom,
I have a few suggestions for your tree, and don't get me wrong, I really like it or I wouldn't have bothered to go through the effort. It reminds me of a tall canopy deciduous forest tree. Serene, quiet, shady.
It is good to see that you have eliminated (or moved?) the small tree branch crossing the main trunk, but the angle that the smaller trunk leans out is too severe now. Can you pull it at point 1 in the photo? If it brings it in too close you can prop the trunk out at point 2. I still would like to see a branch at point 3. With Hornbeams an approach graft should work. Number 4 isn't a big deal, but if you could slowly work towards lowering branches here, at least until the lower approach graft comes in, the right side of the tree would flow better. You still want that nice canopy look.
Last is area 5. The apex of the small tree is turned in and growing towards the main trunk, at least it looks like that in the photo. Trees tend not to do that, especially canopy trees where the goal is to search out what little light makes it through. Lean it out to the left.
You certainly don't have to follow any of my ideas, (but I guess you had to read them
). I think you are on the right path toward making this tree interesting and enjoyable.
Carmen