It still is a good idea, and will still be of great value, as it won't cost anything close to the 7 billion pitched early on.
People keep forgetting that the Eglinton West LRT is getting built because of Smarttrack. Its actually the better decision for that corridor too. Far better.
Right now all that needs to be secured is fare integration at Smarttrack stations with TTC. As long as that happens things are still looking pretty.
8 minute frequencies at peak times is exactly in line with what was pitched during the Tory campaign. Unfortunately, it doesn't seem to be quite enough as it turns out. 5 minute would be much better, but again, at the current lower cost I still think this is a wise investment.
Who knows, if the province invests in some high tech PTC or another set of tracks in the georgetown south/stouffville corridor we might be able to get that up to the coveted trains ever 5 minutes.
As for trains every 15 minutes off-peak, I don't see what the technical limitation for this is, it seems purely based on what Metrolinx thinks is in demand. From a technical perspective, one would think that if we can run trains every 8 minutes on peak through the Smarttrack corridor, we can do it off peak too. You could just run some shorter EMU's during this time every 8 minutes specifically only from Unionville to Mount Dennis. Obviously would need more trains and engineers, staff etc, but if you are running subways every 5 minutes on the weekends and evenings I fail to see what the difference is. Just a different tech.