From someone with a boat and solar panels: cheap solar panels needs cooling, so space between the panels and the stuff they are stuck one. This reduces aerodynamics a lot, which isn't an issue with something going 8 knots max, but I have a friend with a trimaran whose solar panels reduce his max speed of 20 knot to 18 (38kmh -> 33.5), which is why he decided to remove them from his amas and have movable solar panel instead (he put them when he beach or stay at a mooring). My next boat will be a tri too, I just have to find half a million somewhere.

Yes to both, plus freedom to drive/camp anywhere, even far from a guaranteed plug.