This Field Maple was grown from seed and it is around 20 years old (give or take a couple of years) and was originally grown just for fun. This species is coarse in its growth habit and is therefore difficult to get good ramification.
This year it was re-potted into a larger pot, an old Japanese pot, and I think it looks better as it provides an impression of a large tree in a park. The pot is also shallower than the previous pot and this is an improvement.
It was recently shown at the Goulburn Bonsai Society annual exhibition while it was in flower which is a different aspect for maples.