I have ended up listening to the voices of experience and real life testing on the outboard issue. Thanks to John C.Harris and others' practical experience I decided a 2 HP would be more than adequate for Pocketship. I found several instances online of people using the 2 HP Honda for boats longer and heavier displacement than Pocketship (for example the 18' Precision at 1100 lbs). I was even more convinced when the prices for the 6HP Tohatsu turned out to be much higher priced than I expected at local Canadian dealers (more to that story later).
Locally, the Honda 2HP runs around $1000 but then I found the 2.5HP Suzuki for about the same price ($1075). The Suzuki is about the same weight at 30 lbs but has what I think are the added advantages of a true F/N gear instead of the centrifugal clutch on the Honda and also is water cooled instead of air cooled which should make it quieter (which is one of the minor complaints about the Honda). I know air cooled supposedly is less maintenance but I am sailing strictly in fresh water so water cooled shouldn't be a problem. For the extra .5 Hp you get significantly more thrust as this article shows
http://sailorpower.co.uk/21/choosing-an-outboard-motor-for-your-dinghy/. This article is also a good example of how HP does not convert easily or directly into thrust since thrust is dependent on more than just pure HP.
And now for the cost. As I said, locally the price of the Suzuki is $1075 but online in the States it is available for as low as $690. After some deliberation I ordered from the States at a cost of $720 including free shipping to Pembina, North Dakota. A short one hour drive to the border and I will save over $400. The only downside is that the 3 year warranty will not be valid in Canada but I figure $400 buys a fair amount of repair work in the first 3 years of what should statistically be relatively trouble-free. There is no duty at all on outboards coming into Canada, you only pay the provincial and federal sales tax (which is now on $720 versus $1075). I ordered the Garelick 71057 motor bracket and got it on sale for $170, taxes and free shipping included.
If summer ever arrives here; it snowed again yesterday, I will post my real life experience with the 2.5 HP Suzuki.