Re: Adding 3rd pontoon
Straight talk:
Your third toon with strakes may be a little overkill. The purpose of the strakes is to get the boat's nosecones out of the water where the boat can run quickly and efficiently. They're also good for carrying large crowds or heavy weights (without strakes.)
But we seldom see a boat with a cabin that has the horsepower to plane off and use the strakes. If you're running 150 horsepower, you should be very careful, as your boat may not be as seaworthy as you'd like it to be. I hope I'm wrong.
And, you'll need to go to a different kind of trailer with the third toon--and have the outside bunks raised high enough for the larger toon to clear the boat frame. The middle toon also needs to be supported.
Good luck on you project.