As you take crew damage, two (2) of your stats get reduced based on your career.
- 75% crew = Harried, -10%
- 50% crew = Beleaguered, -20%
- 25% crew = Desperate, -50%
Naval Officer: Acceleration, Turning
Privateer: Acceleration, Reload
Freetrader: Reload, Turning
Buccaneer: Acceleration, Reload
Cutthroat: Acceleration, Reload
Besides above penalties, in case you get grappled, you gain Boarding waves according to your current crew (heads). Example: a 'Sovereign' First Rate with 870 crew has about 12-13 waves, while an 'Adventure' Frigate only has 4-5 waves. Every reason to take care of your crew!
This information is provided by the update that PotBS Wikia is undergoing, by Captain Vuur.