While the deals weren't great in early April for those dates I posted, there were Tango flights which would have been cheaper. But there's only so many of those, and more people watching for the flights. What's more, because Toronto is the hub for many flights from other parts of Canada, those flights are very in-demand during spring breaks.
I suggested the one way tickets because they are the same price (no penalty for only booking one way) and you'd get first dibs on those flights out of Toronto. If you wait, someone else might have beaten you to it.
I also watch on Google Flights, and Hopper (the app) to see if those flights would ever come on sale. They didn't. Well, the direct flights didn't. If you're willing to make a stop or two (that Montreal stop is cheaper, I think), then you might find a better price. In my opinion, however, if the weather's okay for flying here, there's no guarantee it'll be okay in Montreal or New York, so I feel like making a northern stop like that is a bit like rolling the dice.
One other thing, don't forget that West Jet flies out of Hamilton. They don't go daily to MCO, but they do have flights, if you're willing to check that, too. You might also look at London, Windsor and even Detroit and Saracuse. I mean, why not see what all the options are, if you're willing to make that drive.