Eglinton might actually be a better transfer point than Bloor-yonge anyways, we're designing it from scratch and have quite a bit more space to play around with. In fact diverting people off BD would probably remove the need to remodel Bloor-Yonge, freeing up however many millions of dollars for other projects. In the medium term the increased traffic could well force DRL sooner than otherwise expected.
I was thinking the same thing. Not only does Eglinton have the possibility of intercepting a lot of southbound traffic along N-S arterials, it also has the potential of distributing the load that would normally be placed on Bloor-Yonge.
One possibility I have been mentally toying with is pushing the short-turn location on the Spadina line up to Eglinton West from St. Clair West. This would ensure that every 3rd southbound train or so leaving Eglinton West in the AM would be empty, and able to accommodate all the traffic from the Eglinton Crosstown. The incentive of being able to board an empty train I think will convince a lot of people to take the Crosstown an extra couple of stops to board YUS at Eglinton West instead of Yonge. This would involve the installation of crossover tracks just south of Eglinton West, however.