Mileage Run Discussion - Flying YYZ-MIA on Aug 19, anyway to make it an MR?

I'm flying YYZ-MIA on Aug 19 for a cruise, so I'm wondering if I can route it somehow to make it an MR (or get more mileage at least)

Right now on the United site I see YYZ-Houston then Houston-YYZ, which seems like a decent option without wasting too much time, how would I go about finding more options?

Returning 24

So you're flying on UA?

You can use ITA to force connections, or specific connections. Doing a search on ITA with your dates, it seems that YYZ-IAH-MIA has the best price, although with very early departure times. YYZ-ORD-EWR-MIA is also possible, with only slightly better mileage if you get the 500 mi minimum.

Sorry forgot to mention, *A, so AC or UA or any other partner airline, and I do get the 500mi min.

The 400~ fare for YYZ-IAH-MIA is gone, any chance of it coming back later?

Also is there a guide to ITA? Havent seen any thread that directly talks about it