What effect does the crew size have in the game?

There are three stats that are shown in the UI, sail life, hull life, and crew.

Sail life and hull life seem pretty self explanatory, but what does the crew do? Is it just another "life" stat that I need to keep at a non-zero amount to be "alive?"

I haven't seen an explanation in the game yet that would hint at what it could mean. It would make sense that if you have no more crew, you're effectively "dead." Certain weapons could target the crew more effectively. You could "equip" different crew to increase your capacity, but still don't know what the effects are.

Do we get bonuses for having a more full crew? (e.g., like firing and reloading cannons more quickly) Are you debuffed when you have less crew? Does killing off an enemy crew allow you to take the ship for yourself?

When it comes to you the player, it seems like there are definitely negative effects when your crew size is reduced to less than half. I'm not certain about all of this but this is what I have observed so far:

1. The amount of cannonballs you shoot in one volley is reduced by half (rounded up). In my case, instead of firing three cannon balls, I'm only shooting two.

   

It also seems that the sail HP also affects your ship mobility in a similar way. If your sail life is less than half:

1. Your max speed is reduced. You can still move, but not nearly as quickly.

Otherwise the hull life is just your main life. If drained to zero, you're dead, though there doesn't seem to be a debuff when you're near zero. These seem to apply to both player and computer controlled ships.