It's a cute idea but it feels a little unintuitive if you're not already kind of invested in this, it feels like there needs to be some kind of snap when something's near the right place because knowing where to start is a bit daunting when you have all these pieces in front of you which all look slightly different sizes and it can be hard without spacial awareness to know what's going on. Maybe drop shadows might help give some of its depth?
We need more model building simulators though and this is a super cute idea. You need quicker movement though so you can actually look at what you're making a model of easier.