I'd say that there are no "absolutes" in terms of which parties it will help and which it will hurt.
I'm not sure that the proposed system will do much to either shift the balance either way in terms of right or left, nor would we want to create a system that would do so. I don't agree with the NDP or lefties in general, but I agree much less with anything that would supress them or otherwise devalue thier votes.
The solution of a "single transferrable vote" seems to be a solution looking for a problem, for the most part. It doesn't address the real electoral problems in British Columbia, but instead tries to manufacture a majority from roughly same amount of people that actually vote. No matter if you use FPTP, PR or STV, you're going to have a credible case for how "unfair" it all is. Democracy is by definition "unfair", but it seems to work better than most of the other options(Well, the only other option I'd support would be a benevolent dictatorship under me, but I'm having trouble getting the support I'd need to impose it.).
The real problem in BC is two-fold:
First, the divide between urban and rural British Columbian's priorities creates a huge amount of push-pull between those groups, with the urban priorities often simply brushing aside the rural priorities on simple numbers. The problem here is that both the rural and urban economies are extremely dependent on each other.
Second, British Columbia hasn't elected a government in a generation, but we've damn sure voted out several of them. Our inability to put together a long range plan since the days of W.A.C. Bennett shows. We tend to swing from one extreme to another, pushing first to the right, then the left, then back again.
I'd suggest that BC would be better served by restoring it's bicameral Legislature, which we were forced to reduce to a unicameral house when we were added to confederation. According to the Canadian government of the time, it was unthinkable for a democratically elected government to have an unelected upper house(I'm far too polite to point out the obvious contradiction in that). If BC were to restore it's bicameral house, with a smaller elected upper chamber based on regions and the current Legislature being based strictly on population levels, you'd see a great deal of long term stability develop.
I suspect that there is something cultural about us British Columbians that means we need the stabilizing effect of a bicameral house. For example, if we elected our upper house for six year terms and kept our lower chamber on fixed four year terms they're on now, you'd avoid having the landslide "about-faces" that seem to be a British Columbian political hallmark.