Being that I'm in the Coast Guard I think it would be in my best interest to conform to the rating plates. South Carolina isn't strict on enforcing the adherence to the manufacturers "suggested" maximum horsepower ratings but some states I visit are.

I grew up running a friends HT BugBuster with a 90hp Yamaha, an 8" jackplate, and Spinelli Bros racing prop. The boat was rated for a 25hp but was WAY more fun with the 90hp!!! That being said I'm way past that point in my life now. I need something that will run well empty, but more importantly that will haul a big load and be safe in rough water. I tend to find myself in some pretty big water these days during not so nice weather. Bigger is better as long as I have enough power to move it!