The question for Marriott is what kind of inexpensive-to-supply benefits will most appeal to their target audience. I suspect this target audience includes two groups -- owners who stay multiple weeks at one resort and owners who reserve multiple units at a resort for a week or longer (presumably for friends/family groups).
VIP lounges and private meeting rooms (for the large family groups) might work but could present problems because it would expropriate portions of the common areas for a limited group. But it would provide a superior experience for certain guests which Marriott can try to sell.
The multiple week guests would like late checkouts/early check-ins, or better, a guarantee of getting their 21, 28, or however many days in a single unit. There is no cost to Marriott for providing this benefit (any inconveniences will fall on other owners). Variations of that may exist already, but guarantees sell to some people.
Actually, I find the entire status level discussion rather amusing -- after Executive level the additional benefits are tiny when compared to the tens of thousands of dollars necessary to acquire them. I will watch for what crumbs Marriott will throw off to induce people to buy even more.