One possibly interesting racial characteristic that might be interesting could be crew 'size' and crew 'efficiency', for lack of better words.
Taking a current 'standard' race (so 100% crew size, 100% crew efficiency), lets say a ship takes 300 crew, and needs 1000 tons in crew quarters for this (totally arbitary numbers).
A race with 90% crew size would only need 900 tons in crew quarters, instead of the 1000 tons.
A race with 90% crew efficiency would need 333 crew instead of the 300.
I would prefer if this was technology dependent instead.
A modern Zumwalt class warship of ~15000 tons have a crew of 140 ( 1 man per 107 ton )
A WW2 Pensacola class warship of ~12000 tons had a crew of 1200 ( 1 man per 10 ton )
And I'm pretty sure our "race" has not evolved that much during the last 70 years in terms of efficiency, or what standards of crew compartments we except. Rather the other way around a crewman today probably expects alot better quarters and facilities then one did back during WW2.
Why not have a separate technology line called "crew automation", or even have specific automation techs reducing crew needs of each research area, by offloading administrative or repetitive work to computers/automation?
It could also be interesting to swap between 2, 3 and 4 shift (12,8 or 6 hours per day "on duty" station respectively), since this would impact morale and crew needed.