I'm currently finishing a stepping-stone MA at UWO, heading to Toronto or UBC.
This isn't true. There's usually one student per year at UWO that uses the MA as a stepping stone. Last year a guy went to Northwestern. The faculty is happy to push you, if you're good enough; plus the small class size makes it easier to get letters. Do talk to Igor, or whoever is running admissions.
It's possible to get most application stuff done in the summer: choosing schools, SOP, research proposal, planning LORs, etc.