Glad you're enjoying the game!
As to the longboat loss problem, the intent is that you only have one, but that's mainly so the player doesn't have to keep track of a bunch of different longboats all over the island and read rules for managing them all. I think it's entirely reasonable to assume the ship could have another if you lose one, or that you could build one in the jungle in a pinch.
Another possibility is to just assume that you grabbed your longboats as you hoofed it out of the village, or that you can enter the village's hex without entering the village itself and retrieve the longboat.
Any of these should work for your purposes without having to add any new rules. Feel free to use any of them with my blessing as designer – or anything else you come up with that feels satisfying.