Looking at this, and perhaps I misunderstand it, but with the phrase “any non-monetary contribution” my instinct is to think that effectively the dollar value of people's voluntary labour would count and might add a significant amount of complexity. Indeed, it might put all kinds of people into non-compliance, especially large, volunteer-based campaigns.
I went through that process myself when the Stephen Harper campaign, which was run on small contributions and many volunteer hours, was up against the Belinda Stronach campaign, a giant machine funded by a few giant contributions and very few volunteers.
I have the concern that we would unintentionally slant the playing field towards those big money candidates. In particular, because it's so hard to keep track of these volunteer hours, it would put the people focusing on a volunteer and populace campaign into perpetual non-compliance with what seems to me to be the least significant part of the cost compliance law. Large dollar contributions are potentially the source of influence and small-scale volunteer efforts are not.