> The beam seems a bit much for my liking, the depth is perhaps
> too deep for easy paddling The length seems too short for getting
> the paddlers apart.

I agree with George, I wouldn't increase the depth so much, the beam is dependant on you and your partner's paddling skills. If you are both highly skilled, then don't change the beam a bit. If you're both novices, make it a bit beamier. You might find, though, that after a season or two, you are skilled paddlers and you would no longer be satisfied with a wide boat. Maybe rent a wide, stable double this season, and build a fast, narrow one for next year.

> I would have increased the length (50%) more and the width (10%)
> and height (10%) less but wat do I know.

Those dimensions would be good, but would your panels fit together properly? I wonder how sensitive a multi-chine boat is to changes in dimension. Maybe you could talk to Nick and see if he could have his hull design software calculate a bit bigger S&G for a small fee.

Better yet, try your hand at a strip-kayak

Good Luck