Thanks for taking a look! Glad you enjoy the theme :-)
Yes, you can choose how many warriors go on from the Crew's Quarters to the Upper Deck. The tradeoff is that those same warriors are also the only ones you can put on the map, since there is no Recruit action (you can try with Parlay, but it's easily defended by the other factions). You have to have some kind of balance between warriors pillaging the Woodland and those working on the ship. Arriving with 15 warriors might sound like a lot at first, but they get divided between the tasks pretty quickly.