I have caught fish on yarn with bead, but the bead wasn't above the hook, right next to it, I m not sure exactly why you should run bead above hook, maybe helps with hook ratio, I were to think fish maybe hooked outside the mouth.
Also make sure you are not casting out really far, the fish are in the rocks, if you cast out too far you will be past the rocks and in the sand. I like to use a rig with a 2 ounce weight on a fish finder rig with #2 or #4 baitholder pretied snells, sandshrimp for bait tied on with magic...
When I fish spinner I usually fish #12 line, and I don't use swivels on #4 blue fox, it is an aggression strike and no need to go super light to minimize lures lost. Drift fishing and float fishing I would stick to the 8# leader.
They have aluminum brazing rods at hardware stores, all you need is a hand held propane torch. I have never done it but seen videos of it done and looks like it is pretty easy.
I would get a 15' smokercraft Alaskan, those other boats you are looking at are too small. As the kids get bigger you will most likely have to get another boat. I can fish three adults out of mine but that's max.