I realized that baseplates have their origin in the bottom surface. My suggestion is to move it to the upper surface. That means when opening a baseplate in the model it lies below the X-Y-plane and just the studs have a positive Z-coordinate (clear?). The advantage I see is that you can start building on the grid without the problem of positioning every part a bit higher (along positive Z according to the baseplate's thickness) and you don't have to lower the baseplate first.

Btw.: Would be cool if Mecabricks would become more "snappy".