Ok, I learned my lesson. Flying from Calgary to Toronto overnight is not a good idea. Sleep is hard to come by in the small uncomfortable seats, and leaving at midnight and arriving four hours later at 6am local is hard when you want to be functional the next day. I had a three hour nap that pretty much negated the point of flying overnight.
Now I just have to deal with this mistake one more time... when I fly home I leave around 10pm and arrive just after 1am, and have to work the next day. Ugh.