Korean Air flies the A380 to Seoul with an easy connection to Bankok. I've never done it, but it gets good reviews. You'd spend most of your miles for two coach tickets...

Cathay Pacific is a good option via Hong Kong and costs a little less. Then there's Delta through Tokyo, but it's the same number of miles as Cathay and finding a seat is notoriously challenging.

Check out the Asia awards chart at AlaskaAir.com:
http://www.alaskaair.com/content/mil...hart-asia.aspx