I hear what your saying on the mileage issue but the old saying is, "you can buy a lot of gas for the $15K your adding to upgrade".
I have a single 350 gasser in our Owens and when I keep it off plane it does pretty good on mileage. Problem for me is keeping it off plane
What can I say, I like to have fun. The trawler will give you more elbow room and a little bit cheaper travel too. Avoiding 2 foot itus was hard when we where shopping, it's too easy to rationalize.
Good luck in your hunt Polo and welcome to the forum.