I have held currency-hedged positions in the past, and achieved positive results doing that. But I've also been on the wrong side of currency moves. I also don't follow a CCP type strategy, so I'm not buying a position with the intent (in theory anyways) of holding it forever.
Personally I don't think it makes sense for most Canadians to currency hedge their portfolios. This is because Canada imports most of its consumer products, commodities (our main export) are priced in USD, and you will always retain some CAD exposure with your job, your bond allocation, your government benefits, etc.
Most of the stuff out there against currency hedging is a bit outdated and is based on the cost issue. In reality, the costs of hedging have come down a lot, so tracking is actually very good and continuing to get better.
There is an argument that can be made for hedging a percentage of your portfolio, especially if you don't hold a lot of Canadian stocks or bonds. However, I don't think you fall into this camp since you are 30% in Canadian stuff as it is.