Hey!
Great thread here!
Keep in mind, Amur maple is an invasive in north america. It is fine as a landscape tree but if it gets into any woodland it is very good at taking over and forcing monoculture. There is one on my property from a previous owner that I will be cutting down this winter... every year it seeds prolifically like you wouldn't believe... giant clusters of dozens all over the tree, I think this thing spreads several hundred, maybe even a thousand seeds every year. Lucky for my area we're in the middle of several farm fields so I don't think they spread far enough to take hold in the wood lots.
Cheers