[KhalilHeron]

I guess its worth noting that this is precisely the direction that Seattle took with many of its LINK extensions.

I cant see an easy way for the line to detour to agincourt from the 401. Could wok at Kennedy commons but it misses the transfer. Also would work east of McCowan you could detour to centennial and/or utsc.
I can see this approach working better west of the spadina line. It can swing down to the 401 from sheppard west and deviate to serve Humber River Hospital or Sheridan Mall