One other thing to note is that electric propulsion in small and medium sized boats has gotten fairly popular. Torqueedo makes electric outboards and inboards, and has systems to drive boats upwards of 100ft. Their small outboards from 2-20hp are pretty cool. Much more costly than a gas outboard, but all the benefits of electric. Your range has more to do with how many batteries you want/need. Li-Ion would be the way to go for weight savings and discharge capabilities over lead acid. Also costly though.
https://www.torqeedo.com/us/en-us/products/outboards
Sorry to post so many times in a short span. I think this concept is interesting and I’m addicted to boating! Check out some boats shows for some ideas. Not quite the right direction, but the WoodenBoat show in Mystic CT is coming up at the end of June. It’s a wonderful event and there are lots of vendors to look at. Many wooden boats get retrofitted with electric propulsion, but they have small diesel vendors there as well that are happy to answer many of your questions, and boatbuilders from all around the country go to the show, so any questions about hulls and ideal this and that could also be answered. I’d like to go again this year. Have skipped the last couple years. Newport is also a huge show with tons of stuff to consider.