The building and jumping into the water that was mentioned works pretty well, and it's also fun.

It's not bad game design to have items sink. The cargo containers floating even when full of metal is a pure convenience feature, and in no way invalidates the realism argument for most loose items sinking. Serpent meat somehow floats when the much smaller boar and deer meats do not, which makes it another convenience feature (no, the bones on boar and deer meat do not explain the difference).