Ahem. Rail Path; do we really want Mx overseeing such a project? (they would insist); their track record is 75M per km of Bike Path, Bloor to Horner is 4km, so that's 300M; another 1km south to Lakeshore (which means a tunnel or bridge over the LSW tracks) and we're at 375M minimum.
LOL
Don't get me wrong, I like the spirit of your idea, but I don't think cycling should touch anything to do with Mx, adjacent to Mx, or over which Mx has even one iota of say, because that will eat the entire cycling budget for the next decade.