I'm just south of you in western Washington State where the gravel road conditions are similar to Vancouver Island. You don't have deep silt or sand, so you shouldn't need low pressures at all. But, you DO have many surprising potholes and rock protrusions in the hard gravel surface.

Your probably running the gravel roads between 20 mph and 50 mph most of the time (not crawling or off-roading), so I suggest reversing your tire pressures to run 32 front and 28 year. A softer tail should help your handling quite a bit.

Rich Smith