Welland Canal going downhill is quite easy. Uphill is quite a bit tougher because of the rush of water into the locks. If the weather is really hot you might want to do the transit at night. It is fully lit and you won't get baked in the locks.
Sorry for the bum steer about the Trent. I have not sailed on the Great Lakes for several years and forgot about the low water levels.
Finished the circumnavigation in early February in Grenada. Have to work on a book project for the next several months so the boat will be waiting for next year.