Just for the record, LRT rolling stock cost a less that subway but carry less people per car.
This is not completely true for the western side, as the subway has a lot of clearance to run above ground north of eglinton due to the excess land available from richview expressway corridor. Granted, it would cost more but not as much as running it underground.
Sorry to contradict all your points but it is necessary to build a system that produces the least number of transfers. It increases ease of use and encourages people to use the system. The only options are LRT or subway the entire way and the LRT was chosen because of lower cost. If I had to give you an example, someone in Scarborough trying to get to the airport, would not want to catch a bus to get to the eglinton subway, then transfer onto another bus to get to the airport. I'm just happy that TTC is building a rail system to the airport. It's long overdue