Maybe a fitness-exercise business could be a good fit? What that big space has going for it, is it is a big indoor space, with incredible water views through the windows, centrally located, and available parking.
Maybe you could lease the space out to an experienced fitness biz who will pay for everything like remodeling and equipment and everything else.
Have you ever been into
www.thefitnessedgenh.com in Meredith just above the roundabout? That place always is busy, always has cars in the parking lot, always has people using it, even on holidays like Thanksgiving and Independence Day. The Fitness Edge has two floors of what is probably leased space.
One big advantage for a fitness biz is that it could bring people to that location on a year 'round basis which would help the other businesses.
The large pier building maybe is large enough to be home to both a fitness biz and a restaurant like
www.anthonyspier.com..... "...experience unparalleled views!" Think they would get annoyed if I stepped inside while holding my rolled up yoga mat, and asked for a freebie courtesy glass of water..........Namaste?
Laconia has incredibly good town water so one cannot blame what's in the water!