Some smaller boat topics I've been considering:
Outboards. I've always used supplemental filtration (Raycor or something smaller) and believe it has helped. In the pre-ethanol days I know it did since I would occasionally drain water. Now all I am sure of is that it prevents the engine filter from clogging. However, part of the mechanism is that larger filters pass the fuel much more slowly per unit area, allowing the filter to remove water particles that would be pushed through or clog the media of a smaller filters. Do others run extra filters?
Solar. I've installed complex systems, integrated with a 120V system and shore power, but they are a poor match for most smaller boats. What with LED lighting and no propane solenoid, our power demands are quite low. I installed a 50W semi-flexible panel, a $25 PWM controller, and a fuse, and it works the trick for peanuts.
Anchoring. I'm tired of hearing about all-chain. I understand the reasons very well and I've used all-chain for a decade. But it's a terrible fit for the smaller boats I've owned. I actually went to no-chain with a chafe leader for my big cat's kedge/secondary and loved it. I wonder if we really need chain at all (I suspect a little is a good thing), but if so, how little? I would also love to see more anchors, other than Danforth/Fortress, that would fit into shallow anchor lockers.
Safety. How do the serious accidents vary from larger boats? MOB is more common. Is there some better jackline & tether system? (PS is running an article on custom and DIY tethers next month.) I know that I have always departed from the standard 3'/6' system for something that fit the boat. I'm adding jacklines to my current boat, but they will probably run only about 30% of the boat's length; that's what I need to stay on-board.
Keeping the companionway dry. A full dodger is too much for many boats. Without a dodger, how do you keep the rain out and ventilate when sleeping? I've rigged a mini-dodger of sorts, but I'm curious how others solve this endemic problem.