I don't like to be negative, but a couple of thoughts come to mind: In 2004, I rented a little 12 ft jon boat with 6 hp motor at Okefenokee and spent a day fooling around in the swamp. I was surprised at how well it did and it did plane cleanly, but there was only myself at 180#, a soft sided 6 packer with a couple of blue ice chunks and a couple of Pepsis and my camera & light tripod. Total load in the boat was under 200#.
You put more gear and another person in that thing and I'm very afraid you'll be disappointed. If it's only rated for a very marginal 6 hp, I'd seriously look into upgrading construction to allow at least a 9.9, which you can still carry away in one hand. That extra 1/3 hp increase would make a huge difference.
Also, I did a lot of boat work some years ago in the Pacific NW and built a couple of small ones. I don't remember sources et al now, but the big whoop-de-doo was for "CVG" Douglas Fir. (Clear Vertical Grain) Hokay, I jumped on the band wagon and for a project, I special ordered a 16 ft CVG Fir 2x4 at a lumber yard. Don't remember the price, but it was horrendous.
When it came in, it was a really beautiful piece of wood....then I tried to pick it up. I swear that board was made of cement, prob'ly with rebar in it. Migawd, it was heavy.....and I never did use it because of that.
My point is to personally check each piece as you buy it - even same species can have widely varying weights, depending on tightness of grain, moisture level, etc. Choose the lightest of each.....it can really add up. If you have a source, maybe even look into Sitka Spruce. Good Luck.