I have a swing back so I already have a lot of storage buts it's just silly how much is in our center toon: 1 large bundle of 6 life jackets, 2 table posts and table tops, two six foot pvc poles for beach frisbee game, four support poles for cover, four folding bag chairs for the beach, four oversized bumpers, a full size broom and a couple xl ski vests for adult tubing. It's horrible trying to get at anything at the bottom but we'd have to leave much of that behind without the tube storage.
By doing this we keep the seats open for kids life jackets, bags, towels, food, sunscreen and bug spray, blow up water toys, dog toys, tools, flagpole, boat cover, inflator, etc., the stuff you need to get at frequently.