I don't know how true this is, but it seems to me that the early Charles River builders put long decks on their canoes (the "courting style" that tended to pull the couple closer together) and perhaps the builder of this canoe was asked to put short decks on the boat for a customer, and chose this ogee-style... perhaps this builder rarely used short decks (?).
As far as the seats are concerned, is it possible someone routed-out the area where holes once were, in an effort to make the seat "easy" to cane? If this was the case, you might feel holes on the underside of the seat frame.