This process sounds a lot better than what we did a couple years ago when we were working on that game. Our process involved Voxel Shop https://blackflux.com/node/11 and a few steps. I can dig up the notes if it's interesting, but it looks like your process is better anyway.

I've also heard that this asset might be useful, but I haven't tried it yet: https://assetstore.unity.com/packages/tools/modeling/magicav...