Thank you very much for your feedback :D
I must admit that simplifying the real physics of a boat — combining hydrostatics, dynamics, and aerodynamics (sailing upwind) — has been a challenge, and still is! I need to refine the boat itself, because even though what’s displayed is just a cube, under the hood the engine actually takes into account the waterline, the hull length, the sail efficiency, etc.
I think I’ll “cheat” a bit on the speed by making the boat move faster than the real calculated speed, and also by tweaking the FOV. Do you have any knowledge of sailing, especially points of sail? Because with good sail trim, you can actually go quite fast.