To me the current shape is appealing. I would suggest you think about finished height of the tree before chopping it, as the trunks are the same width pretty much back to the main trunk. If you plan on a tree about twice as high as this one, you might get away with where the chops are now. Can you plant this one out? I think you have a lot of growing to catch up the continuation of the trunks in size, so it might be helpful for a while. (But I don't know TP culture, so I could be wrong that they are faster in ground...) I suppose you could carve some of the trunks down, to help with the transition. But I don't know how these do with deadwood, or if you even want deadwood on this tree.
This is just my opinion, to me it looks much like a natural maple.