Hi Mike,
I'm curious about your rudder casting/bushing issue. I believe the original castings were used as either a metal to metal contact with the rudder pin, or else used the thin nylon liners. In later years, Hobie developed thicker nylon bushings that could be inserted into the castings after the holes were drilled out a bit (I did this to mine not too long ago). Once I drilled out the holes, it took some tapping with a hammer to get them in, but at least they're a nice & tight fit. They're Hobie part no. 8062001. Only $10 to replace a set of four. As I recall, mine required a bit of shaping to fit into my original castings - specifically, I had to cut down the lower one and then file the "lip" down to get it to fit over the gudgeon.
https://www.backyardboats.com/getattach ... llers.aspxThose stickers are probably baked on... good luck!
The side walls and decks of the hulls do have a foam core, it's the bottoms, lips and bows that don't have foam. The flex means that the sticker is probably hiding a puncture that goes through the outer layer of fiberglass to the foam core, but not all the way through. The moisture that has gotten into the foam has probably allowed it to start breaking down or lose it's adhesion, creating a soft spot. You'll have to sand down the area with a good taper, then build back the fiberglass and sand it smooth. Then you'll probably want to do the typical soft spot repair (drill breather holes and a center hole, then fill with epoxy), let it cure, and then cover the area with some new gel coat.
The pin-prick holes I believe come from the age of the gel coat... or perhaps it ended up just a bit more porous or with some small bubbles when they sprayed the gel coat initially... remember, the gel coat was laid into the mold first. I don't think you necessarily need to add a layer of gelcoat. If it bothers you, you could sand it down some and then add a layer, but that's probably more work than it's worth.