5 man crews would be interesting, as each ref could watch a position. This wouldn't likely lead to better refereeing as its easier to lock into two guys than it is certain spots. You'd have two refs up top, two refs in the corners, and a ref on the baseline. The baseline ref would watch the centers, the two up top would watch the guards, and the two near the corners would watch the forwards.
When possession switches, one of the refs up top would rotate to the baseline and the previous baseline ref filling that refs spot up top. Therefore you'd have two refs watching PGs and Cs, two refs switching between SGs and a F spot, and one ref staying on one F spot the while time. This is a good thing because that ref would have to run the most (corner to corner on the side that rotates to the baseline)