Lots to do, some of it touristy some of it just plain fun.
Best thing besides just walking around and people watching was the paddleboats at the basin bonsecours. We went in the evening towards sunset and it was just a peaceful and fun way to watch all the activity of the port and still relax and be on the water.
Great for couples or even families with kids, lifejackets available but not mandatory. about $17 canadian gets you 30 minutes, but they didn't really enforce it so you don't have to watch the clock.