I am a long term Marriott Reward member (3000 nights), live mostly in Malaysia/China. I have tried all five chains from US, Marriott, SPG, Hyatt, IHG, and Hilton. Here is my 2 cents:
(1) Marriott Reward is the best program for top tier elite from location availability, suite upgrade, free lounge access and free breakfast buffet stand point. I received suite upgrade more than 90 percent of the time at Marriott/SPG. SPG was initially my backup plan. Most Marriott hotels in Asia even the Courtyards have executive lounges. I don't have high requirements for food, so free food and alcohol at the lounge is fine with me.
(2) Recent years, I stay quite a bit with Hilton(Hilton Diamond), my new backup plan. The disadvantage of Hilton is that there is no redemption chart, properties at peak time can increase redemption points drastically. Also, Hilton points are less valuable than Marriott points(see TPG valuation), hotels at Hilton cost more points for redemption in general comparing to Marriott. That said, Hilton has put in an effort to increase point accumulation rate for its members in recent years. Currently, point accumulation at Hilton is the fastest.
(3) Not enough Hyatt around. IHG is not very consistent in my view.
(4) In general, you are much better off spending your money or points in Asia in these hotels rather than spending them in US or Europe.
I know Accor has good coverage in Asia. Will give it a try if top tier elites can get suite upgrade, lounge access and breakfast buffet. I am still doing my home work on Accor.