How many cities have funky islands a stone's throw away from their core? I love the islands and make it a point to visit atleast twice a year. If you can avoid the crowds, this place can be very beautiful in many ways.
The islands have decent beaches from where one can see spectacular fireworks directly across the strait (Exhibition Centre / Ontario Place). There's a nude beach too which I haven't checked out (yet). Rest of the islands are filled with criscrossing trails and walking/biking paths.
I find that the views of Toronto are very beautiful, especially after dark on a calm night when the city's skyline reflects on the water below.
Western tip of the islands is home to a cute little airport whose growth, if not checked, will soon gobble up the narrow stretch of water separating it from the mainland.