NDP have already (and continue to) moved off the "fringe" and towards centre/moderate. I'd also like to note that the vast majority of countries that out rank us in all those livability/education/life expectancy yadda, yadda scores you see come out every year tend to be more socialistic (ie: left) in nature than us, not less.
This thinking that you can't have quality, well run social programs AND be fiscally responsible is idiotic. Numerous countries around the world do just that and out rank us on a great many livability/quality of life/education/health care etc standards. Why you wouldn't want to emulate that is beyond me.
Germany being an especially good example of this. They're pretty much propping up the entire EU and have excellent social programs, vast "green" initiatives and higher food/farming standards while retaining quality industries, manufacturing, tech etc
I seriously doubt that the NDP, or even an NDP contaminated united left would leave our country with quality industry, manufacturing, tech etc. I have yet to see an NDP government that doesn't call for the social programs you call for but at the same time they all tend to want to raise taxes on business. Higher taxes, tougher environmental laws, stronger labour rights, and more regulation in general might be populist but it's a sure fire way to drive business out of town. Especially the oil industry which is a favorite target of the left despite it paying massively into budgets (so much so that every time natural gas prices switch our own provincial budget takes a massive swing and our revenues from oil and gas are miniscule compared to the fed.).
Even the ultra low tax, high deficit, credit bubble forming conservatives are improvement on that. If you recall I even made a thread complaining about conservative economic policy but if all your trying to do is beat the NDP at that it's not a very high bar.
I have yet to see the NDP stray from any policy that wouldn't sound as though it came from a mouthpiece of big labour.