The Islands Trust should take this one on. There is a monster house being built on South Pender ALR (Agricultural land reserve) land currently.
However, a recent posting to a food listserv made the point that these large houses are only a symptom of the real problem, and that one day multiple families may be living in these houses, or building big houses of their own. The affordability of farm land, and the demand by those wanting estates, subdivisions, industrial parks or investments (or regional, national or recreational parks - and a new one called an agri-park!!) have driven up the price of farm land. The rule of one house-one trailer seems limiting to those who think the solution is to put multiple people on the land (although I have heard some of these groups say that their true desire is to be on the land, not necessarily farming, so that could make them part of the problem, too). The Ag Land Commission puts the limit on primarily because putting multiple houses on a farm takes away arable land from farming (footprint issue) and it also drives the price of the farm up for the next buyer.
I think such a complicated issue won't have a simple solution.