Attach that knife and it sheath upside down so that you can draw it with either hand. You don't specify what model of PFD you will wear, but consider one with enough pockets to hold marine flares and other items (SPOT?).

What are your water temps like? I would think something a little warmer than shorts would be appropriate for Ontario. Are we talking sea kayaking or whitewater? I am thinking like a sea kayaker.....