Neat tree! This looks like a fun project.
This is the perfect time for a trunk chop and large branch removal. Since it’s in the ground, strongly established, and has big extension growths I know you can take it all the way to the ground and still get a nice flush next year. If you specifically know your yard has disease issues or if you have grown tomatoes nearby then sealing the cuts makes sense to me.
Just know though that these highly vascular deciduous trees are more likely than not (when so strongly resourced like this) to put on coarse and chunky growths in their first flush of the year. You’ll have more luck producing finer twigging and shorter internodes in the second and third flushes of the year. These flushes are best prompted and controlled by pruning.
(apologies if any of this is redundant; it’s a mix of my experiences, the lessons of my teachers, and guidance from other local practitioners)
For our climate it’s roughly late May to early June when the new foliage is hardened off and we can remove the new growth back to the best nodes for position, orientation, or length. Because you’re planning for future growths to be preserved then you ought to leave an extra node or two on each branch (in late fall pruning) to draw off the excess, early spring energy that can blow out to internode distances of 5–8 inches. If you’re always pruning back to the ideal node in the tall then you end up with coarse twigs on this sort of species.
The third flush (or second pruning) is wholly dependent on how the year went for weather, your technique, a relative read of the tree’s capacity, and just generally your risk tolerance. I think this is usually successful when done between the third weeks of August or September. You can prune back to the best new set of nodes yet again.
Regarding identification, this looks to me like a vine maple, but I’m not declaring this as fact. I love them equally well as the bigleafs.
I have a handful each of vine maple and bigleaf and think I see more of the vine (circinatum) characteristics between bark color, internode distances, bud a and branch shaping. My bigleafs get dark maroon reddish or almost purple colored bark, and not this sort of ruby coral greenish blend that we see here. The bark texture also looks different here — I can’t quite describe it, but this matches my experience where vine maple bark ages a bit more like the Japanese maple bark. For a rough description, I’d describe bigleaf bark aging to be more similar to Norway maple, sugar maple, cherry (minus the papery quality), or plum.
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