I'm not particularly familiar with this part of the countryside. In fact, this is the first time I've ever been in Ottawa, even though I've been in Canada for 46 years.
What works in Alberta is that Canadian Pacific's line to Edmonton is a secondary main line. It is not a main line. The main lines run east-west. In Ontario, you have the main lines running east-west.
I have given this some vague thought, with no basis of foundation, as to whether you can find some way to consolidate the CP and CN usage of track and find abandoned routes or abandoned rights of way that are still available to get you in and out of the cities—because that's your big challenge, getting in and out of the cities—if those options are open to you, or building alongside either the CP or the CN.
John is from Ottawa originally. He's much more familiar with the countryside. So I'll let the other expert speak.