I too am a fan of the US Interstate system however, having recently completed a road trip down south I noticed the roads are not as well maintained as they used to be. In years past the Interstates were almost smooth as glass, but that's no longer the case, probably to do to the recession and the nation's high debt.
Another plus with the Interstate system is the speed limits are usually 70 MPH and in Utah I saw areas where it was 80MPH.
In comparison the TCH in years past really was a national embarrassment, especially between Banff and Revelstoke and other stretches all the way to Vancouver, but it is getting better, slowly. Same with Ontario, I remember travelling there years ago and the shoulders were gravel and no dividing lanes which is ridiculous for a national highway, but IIRC that's being addressed as well.
It would be great if the TCH was a superhighway right across Canada with a speed limit of 130 KPH, but I understand that's cost prohibitive.
In a perfect world we would adopt the Autobahn system which is bar none the best road system I have ever driven, but even a petrolhead like me wouldn't put up with the taxes to allow that to happen, so I'll accept something in between.
At the very least we should have two lanes divided in each direction and minimise traffic lights when a bypass is not feasible.