sounds like you are going to have some fun.
here are a few things that i learned when i finally put my mini in the water last summer, it is small, but was fun to drive, the hull is 11 x 4 foot w/ 16 in. sides . I hope that with 3 more feet, you can have a little more free board that what i have.
i ended up putting 8" side boards on the back half. these were needed to keep the water out when turning.
the motor with the gear box weighed in at 70 lbs. and rudders came in at 12 lbs ea.
i think if I went to 1 lighter rudder, hanging off the back it would make a big difference on how it sat in the water.
it was a kick in the pants to play with, with my son or I driving, never had any water come in. but when my better half, took it out. she was not a speed demon. and when she would slow down to turn, water would come over the back. ( kind of scary) don't really think she would like to swim the couple of hundred yards back to the shore.
this winter/spring, i will attempt to widen it, up to 5 or 6 feet. to get more flotation. or build a new hull 5x12 with 20 in. sides
the times i took it out, i spent more time getting the prop pitch set to match the RPM's, and my jetting was giving me a few fits, until i realized that one of my chokes, was not seated properly. but out playing on it always put a smile on my face.
i put just a few videos on my build, and you can see how it acted. my oldest son treated it more like a jet ski. and even though he put it though the paces, there was a few times, we thought he was going to swamp it. but it would jump right up on step, and he would be off again.
never did trust it in the rivers where i live, (yet) i still am pretty green behind the ears, when driving it.
but i am excited about the few mods that i will be doing this winter and will see how next summer goes.
it will be fun to see how your boat comes together.
so have fun and enjoy the journey.