Most people think of me as skinny. When I was at decent cycling fitness, I weighed in at about 82kg. Add typical commuting load (laptop, clothes, food, tools, lock+luggage) and you are not far shy of 90kg.
Really, I wouldn't want to commute on a very reduced spoke count bike. It only takes one twig, or stupid rat (I've had both) in the wheel to seriously ruin your journey. Take one spoke out of 32 and you'll be fine. Might even manage that with a 28 spoke wheel.
Lower than that is pushing it.