The streak on the starboard hull is caused by trying to sand off an epoxy drip out of the outer gunwale. Me walking away from the project after an epoxy job to avoid breathing fumes, also results in these issues. I think I will just fair it a little and repaint.
Started using the 403 filler adhesive filler. It works very easily, spreads nicely, just have to be very careful mixing it because the fibers are very light and will either blow away or jump out of the mixing cup.
Filling all gaps with 410 and adding a fiber tape with unfilled epoxy should beef up the structures plenty. Still quite some work to do before finishing her up.