I haven't tried any in a pot, though I'd like to. I'm not sure why they aren't more widely used. Maybe they don't like being containerized, maybe the leaves don't reduce, and maybe they just aren't a terribly long-living tree.
From growing a few in the yard, with a plan to pot one at some point, I know that you can chop it down as hard as you want, and it will bud from the trunk. They grow very fast in the ground here, faster than trident maples.
With yours, I would consider at least removing the middle of the three main branches, and shorten the remaining two by at least half, if you want a finished height approximately the current size. A less-conservative approach is to remove the middle branch and another, so the last remaining branch is a second section of trunk, adding some movement and taper. Even better: chop it down to about 6" tall and let it grow a new leader all year to add a little movement and taper lower in the trunk.
