I hear you!
Toronto to Stoney Creek (South Burlington) isn't that bad, but the stretch along the QEW North Service Road is brutal! It gets better after Jordan.
My Partner and I did the
Niagara Bike Trip and really loved it.
I'm doing a Toronto/Port Dover trip on the second weekend of September. I'm cheating a bit my taking the GO train to Oakville, then following the Waterfront Trail to just South of Hamilton Bay (after the lift bridge), and then cutting up beside STELCO to Burlington Street and then up the old Toronto, Hamilton, Buffalo rail trail to Caledonia. I'm taking the Lynne Valley Trail to Brantford and the Brantford/Hamilton rail trail back to the Steel City, then bike back to the GO train for a well deserved ride back to the Big Smoke.
You might want to consider both those rail trails for another run.
Drink before you are thirsty
Eat before you are hungry
Rest before you are tired.
Do those three things and touring will be enjoyable.