Open to any ideas on design for this maple.
The design that you have works well for me. I see (pic 1) a large billowy mass on the left and a subordinate mass on the right. If you clean up the structure focussed on removal of flaws like crossing branches and opposing branches and wire the remainder into their own space. You can then work on improving ramification with post harden pruning and defoliation techniques.
Nice tree - I would try to tilt the tree and see how I could remove one of the branches ; elongate the tree with nice slender movement and further cultivate the tree to get a ticker trunk