Maybe the electronic parts in the ceramic shapes could be arranged in a way that they connect through gravity. If the top and bottom are not parallel, but rather cone shaped, they could kind of “fall into place” through gravity.
Like the sunflower seeds:
So this would be upside down:
If the top surface was elliptical, it could be easier to mark the plus and the minus, because it could only be put in one direction, not the other:
The 6-edge mockup:
Minimum 3 edges:
