Large amount of work, it gives me a nice insight about Image2Voxel, which I never test out before. What will be worth to add is an real case scenario or some actual benefit that it'll produce in your opinion.
I only took it to the paper/whiteboard design stage. The problem I had was voxels became wildly more memory consuming when you introduce more than a binary there not there type. I was looking at 10-15 megabytes in memory just to describe a simple 2x4 brick with the min resolution and it still worked as a lego. At the time I was lucky I had 96MB... The exe was pretty small (maybe 1-2MB total). The data on the other hand I could not find a nice way to compress it enough to work without a few dozen bricks filling my memory space. Mostly I got bored with the project and moved on.
The 'voxel' style has one very nice quality about it over the ldraw cad system. Unintentional gaps are nearly impossible to have and overlap is dead easy to find. Correct overlap lets you do interesting things in that you can intersect things correctly and it will just work on the snap grid. The ldraw system has to jump thru a few hoops to make it look like it is working. The effect is the same but more of a pain making sure your floating point is correct. ldraw has a nice quality in that rotating an object in freespace is 'cheap' and you only have to rotate a few points. Whereas a voxel system like I designed you in effect have to rotate everything.
At this time the ldraw system is the choice to use if you are doing this though. When I built my system there were maybe 200 different bricks total. Now there are thousands.
With ML detection you can get a good ways decently the hard part is 'hidden' feature. Depending on orientation with some pieces they will hide features. For example a 2x4 flat looks the same as a 2x2 flat on many orientations (extreme example but shows off the effect nicely). I have seen some people use tumbling the piece or a few cameras to mitigate the issue.
My proj was more along the lines of how do you represent a single piece in memory without using a planar point system such as what ldraw did. I had toyed with the idea of converting between the two systems for memory reasons. But it became compute/IO expensive very quickly on collision detection with other pieces.