Thank you both for your suggestions!
Actually I wouldn't even mind some snow, so maybe not-quite-spring like now is my perfect time to travel.
Checked out the CNTower online, and I chuckled how the edgewalk package includes a "ticket to re-enter the tower". Like, if they didn't gave you one they would stand all inside by the window and stick out their tongue all "nuh-uh, nope! You're not getting back in here, have fun and don't fall off the ledge at night"
Maritime provinces look nice too, in fact I like their architecture better than Toronto's from what I gather on pictures. The falls are amazing, and apparently not that far from Toronto, so I could stay in one place and take a day trip to the other. (I'm going to check whether there is some Canadian equivalent of Interrail, where you have one ticket and may use all trains or buses in the area. A round trip seems the best deal to get to know the land)
npixelz, I love your avatar! You look like a cyber musketeer.