Here’s an image from a guardian post showing boats used by refugees to cross the channel from france to england:
Most boats are inflatable mono hulls. AFAIK, the safest* boat design is actually a multi-hull, like the handful of catamarans in the picture.
Hard to fail thinking that perhaps making safe DIY boats could be a useful way to cross all sorts of bodies of water.
Some say in certain conditions mono-hull are safer. These conditions presume either a very fast catamaran, or a self righting mono hull – nothing that i think relates to the situation.