Having not looked up anything about USS, I think like this: the libra symbol is the scales. I think of it like weighing decisions, which is funny since libras are seen as indecisive. Most decisions come down to what the heart wants and what the brain wants. A person carrying around scales with a heart and a brain on them. The person has a bloody hole in their chest and a surgical cut through their head, implying they are weighing themselves.
To me, the podcast made it seem like the zodiac themselves might be on stages with minions below, so the character designs could be really intricate if they won’t be walking amongst the crowd scaring.