Whipping it into Google Maps this is what it looks like. To go diagonal it would require a deep bored tunnel but there are obvious benefits in terms of trip time compared to trying to follow the street grid.
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Very interesting! I can see several benefits coming from this alignment:
1) It would solve the problem of Lakeshore West passengers not having a convenient route to Pearson (without going all the way into Union I mean). Transfer from GO to TTC at either Humber Loop or Roncesvalles, depending on where the stop is located.
2) It would be a God-send for the Mississauga Transitway, because it would be feeding directly into a downtown-bound subway, instead of the roundabout routing into Kipling. Ridership on the Transitway would boom.
3) Etobicoke Lakshore would boom even more than it already is, because the Lake Shore streetcar (which could relatively easily be upgraded to full LRT) would be feeding directly into a downtown-bound subway station.
4) It would tremendously reduce the pressure on the outer portion of Bloor-Danforth, because most of the Kipling-bound bus traffic would transfer onto the DRL, not B-D.
There would be only one change that I would make though: I would put one more station on the Queensway (at Islington), and then have it curve north to intersect the B-D line at Honeydale instead of Kipling. A major terminus like that really needs to be built from the ground up, to not be a hodge-podge. This was the same mentality that lead to the construction of Kennedy Station when the SRT was built, and I think it worked well (the design could have been improved, but the idea behind it was right).
That would also further encourage development along the Queensway, which I think is primed for massive redevelopment given the right catalyst.
I do have to say though, there are very few maps posted on here that are really a smack to the side of the head in that they're so obvious but no one has thought of it, but this one did just that. Well done!