There's an asthetic tempation to make everything look super-high tech. But I think if things look superhigh tech they actually look worse.
This is a dieselpunk universe. Some of the house lawfuls don't even look very high tech, and they should be technically ahead of everyone else. Bretonia is steampunk, Rheinland is chunky dieselpunk, Kusari throws these Meiji era asthetics onto its ships.
I'd love to see a xeno ship that looks like this:
THE SYNDIC LEAGUES
(A co-operative of Rheinland's outlawed trade unions, determined to take the underworld for themselves.)