I would re-read Scott's position. Personally if you want to stick with the stock rims I would choose a very tall tire like a 255/85 16. Reason is you get that added floatation from the long contact patch while not having to worry about going to aftermarket rims to prevent rubbing on the control arms and you won't have to worry about rubbing on the body mount. Mitsubishi uses a 235/85 16 on their cars that race in the Dakar rally, and the rally is full of really deep sand and dunes, they have also won the race 6 years in a row, and seem to make easy work of the dunes.
As quoted from Sahara Overland, a Route and Planning Guide by Chris Scott (2004, ISBN: 1-873756-76-3):
"...Note that it's the diameter or height of the tyres that makes the difference in sand, and not, as many imagine the width... For the desert, you want tyres with a high aspect ratio of around 80 because this represents a taller sidewall so corresponds to added ground clearance when firm, and a longer contact area when deflated"Traction in soft surfaces: It is a common misconception that airing down a tire for off-road traction only makes the tire contact patch wider. That is not the case. In fact, only 20% of the increased contact comes from the width. 80% of the increased contact patch comes from the tread patch becoming longer. A tall, narrow tire allows for a very long contact patch when aired down. That, coupled with the minimal frontal resistance (area), negates much of the downside to narrow tires in flotation situations. The taller tire allows for a long contact patch and still maintains good ground clearance.