I plan to be an engineer and fly cruisers almost entirely. Looking at the traits, the following seem the best to me:
Efficient:+5 bonus to Starship Shield, Engine, Energy Weapon, and Auxilary Systems Efficiency
Leadership: +15% Repair Rate
Warp Theorist: +10 Starship Warp Core Training
Only humans can take leadership, but in doing so they are also forced to take the crappy +expose damage trait, in effect giving up two good talents to get leadership.
Is the leadership trait worth that? Once i'm in a tier 5 cruiser will that +15% really matter when i have that huge crew? Playing a heavy cruiser in the beta, my passive hull regen didn't amount to much if i was actively taking hull damage so i'm not sure it can compare to just getting the other four super good traits instead.