Many of us have been building and then noticed that the pattern of Ceilings or Foundations is out of wack. Ceilings placed in a mix of directions cause my tribe mates to twitch. I noticed while placing Stonebrick Ceilings last night that they actually have four different alignments dictating direction of structs and crossbeams. you already have a marker on walls etc showing the outside face for easy placing. Why not put an arrow on one face of the ceilings and foundations so it becomes easy to align them all perfectly. You only need to mark one edge/face. Then people can say “Align all ceilings north” and the whole base will have the same pattern.
To make it easier, you could have the arrow indicator show up on any already placed ceilings/foundations near the item you are placing so that people can see what they are already aligning to.