I don't believe there is any question that Maui has the best trading power. But it also has the highest price & MFs. It also may have the most troubles in trying to reserve a high demand week.
IMHO, Don't buy a high priced Marriott for its trading power, but because it is where you want to visit. If you're buying a Marriott for trading mostly, the collective thought here seem to be a resale, Williamsburg Manor Club, plat with lockoff, gives you the best trading options at the best price.
Good Luck