If you are downtown bound without a car, I second the Distillery district and Kensington. Never been before? CN Tower for the view (skip the overpriced revolving restaurant) and Riplys aquarium near the base. Summer’s gone, so that rules out some stuff.
There’s lots of great restaurants mixed in and around the core. It’s been decades since I’ve lived there so I’m out of the know as to what’s hot. Last time back, Queen street was a bit of a hot spot for nightlife food & drink. As mentioned, tt’s been decades since I’ve lived there so maybe some locals can chime in there.
If you have a rental car and don’t mind milage and a road trip, it’s 2 hour drive to Niagara Falls and Niagara on the lake. (Shop and eat in the latter, visit some winery's and enjoy the pretty drive along the river to see the falls and then head back to TO. (The falls is really the only good thing in NF unless you like the hokey fun houses and other cheesy attractions found just up the hill)