Oh very interesting! I have a soft spot for aluminum canoes. Many fond memories of in a Grumman. Is the stability more from the hull shape or from the sponsons or combination?
Shape of its bottom more than anything else giving it tremendous primary or initial stability. The sponsons only come into play under larger loads than usual.
Duck hunters use Sportspals for a jump off platform for large labs and other breeds, grab them by the collar to hoist them back inside the canoe.
What you end up with is a single vessel:
1) that can be solo'd with a central seated position using a double ended paddle;
2) a tandem platform for two large men and all the gear you can store;
3) and, with the square stern models, ready to accept either TMs or small outboards;
4) and, you can paddle standing (I use a 280 length) all day long.
I often go out over a mile standing, back home the same way.
Me and one of my grandsons below coming back in. Note the folding chair I carried out. If you think a kayak seat is comfy, try one of these!!!