I like the way y'all think because I've thought the same things! :laughing:
Unfortunately, my garage is in it's fall-zone and I've put off good judgement for about 7yrs just because I hate the idea of cutting it down. The house was built around 1790 and the tree almost certainly saw that happen.
I actually brought out a chainsaw carver I know. He said with the trunk still attached to the roots any carving he does will only last a few years. In the and we decided we wanted to put another tree in anyways because we rely on the shade.
There is a reason the new tree needs to go in the same place. Hidden behind the big maple is a 6" DBH Sunset Maple I about 6 years ago. About 4 years ago a kid I had working for me nearly girtled it with a weed wacker. I may still grow ok an want to give it appropriate space.