Float flying:
I started my career flying floats and now I live on a lake right beside a busy float base. Some of the things I see drivers doing now would have been subject to severe tongue lashings or WTF was that all about and I just shake my head. The sad thing is that I see this stuff on a daily basis so it obviously has become the norm. Most are small and under airmanship but still the abuse of the aircraft makes the hair on the back of my neck stand up.
We would never do runups if it was windy, check mags and run prop through at taxi RPM and do a normal runup when we had the luxury of glassy water. Power applications is the worst aggravation, when prop can't keep up that is the worst. It's like someone just kicks the throttle. What happened to gentle -- lol --
Xwind techniques but that seems to carry right across the whole board. Water handling and obsession with step taxi. Finally gusty wind landings. You can't dick around and it's such a simple thing. Just find a cat's paw and land in it. So simple just pull the power just as you are about to enter it and hang on. One of 2 results, touching down in the gust and grease it on or come out the other side and you bang it on. The result you are on the water where you wanted to be and not dicking around floating from gust to gust trying to wrestle it on the water and running out of space. My simple rule for landing, floats, wheel or skiis, is hit the target.
I never flew a boat so chuck that's your bailiwick.

A lot of this is about our love of "vintage" aircraft and large flat and round engines. Airmanship from these days is still a good way to approach current aircraft as well.