Gabler
Masterpiece
Interesting. I think I would have removed some of the lower branches at this point, but I guess it depends on what the final plan is. I do like the chop you just made.
I probably will remove some lower branches, but for now, it's my understanding that they'll help promote good taper, so they stay. I can't un-chop them, but I can always chop them later. It'll take longer for wounds to heal, sure, but generally, these maples heal fast and smooth. A finger-thick branch pruning scar will heal over with just a year of unrestricted growth above it. At least that's been the case in my limited experience.