Depending on where you are staying in Venice, you may be looking for a restaurant that doesn’t involve a long and winding walk or a boat trip! This was just 150m from our hotel, set alongside a gondola route, and we sat canalside. Make sure you clean up/dress up - I’m convinced you get the best tables if you look like you made the effort.
We drank Orvieto, had Gnocchi, spaghetti all seppa (squid ink, black) and scallopina. All delicious, watching the world float by, with occasional singers on the river. Lovely evening, expect around 30€ per person.