Re: longer hitch for launching boat
We had a trailer with a built in 10' extension so we could float the 21' CB boat I grew up sailing as a teen. Pretty common way to make it easier to get a boat in and out of the water.
I do agree that a hitch extension is not the best option, extending the trailer tongue is the "BEST" option, but for a short 100'/yd trip typically at best, with speeds under 5-10 mph, should not be an issue!
She drives me boat,
I drives me dinghy!