Dear Devs!
We have 3 usables for our ships... missing the 4th one.
U forgot The Sauerkraut!
Famous Captain James Cook used it and brought his Expeditions to success.
Instead of Rum SK should be in hold to recover from crew losses. The cabbage has to be farmed with a new building.
In future Rum could be used to buff morale and influence some skills positive and some negative, such as the way the different alcoholic upgrades do it permanent. Rum or other alcs could do it with timer.
Here u find the historic background:
https://modernfarmer.com/2014/04/magical-sour-cabbage-sauerkraut-helped-save-age-sail/