You might as well redeem for an upgrade... everything else sounds useless in terms of value.

You can go through some Chinese Travel Agencies but the price you get will probably be like USD 400 for 40,000 miles (so they can earn a profit from you to sell to someone else). Go through some chinese forums to do the transfers will allow you to bump that to approximately USD 600-700 for 40,000 miles. I am not going to list them cause I think it's not allowed on this forum and you need to know mandarin regardless... but just to give you an idea on how much you will get.