I think the key is variation, at least for beercan series. If you have 15-20 races a series, throw in 3-4 triangles and maybe some downwind starts. A whole summer of W/L races is exhausting and can get boring.
the whole "umpires can't be expected to police kinetics, so we're going to allow all the kinetics" thing is so freaking lazy. just ban it and let the flicking commence
river not a lake, but here's "Fair and Square" from the Frostbite Yacht Club in Essex, CT. I would think a smaller pontoon type raft or "pahty bahge" (https://directboats.com/la610caelpa.html) would do the trick