I've found with award travel being "dynamic" that 400,000 miles to work with is insufficient for award D1 travel to Asia.. You are traveling over the Xmas holiday season so fares will be elevated using real money or Skymiles. If you want to enjoy the vacation you are planning, select a location and shop for fares across many airlines and book the travel that fits your budget. I've been a loyal Delta customer for decades, 2 Million Miler etc....I've recently come to the decision that chasing the accrual of Skymiles is not my best travel choice.

For example, I tried to find business class award space in July from USA west coast to BKK. Noting available with the 500000 Skymiles I have to work with. Delta had fares around $4100 in business class, Japan Airlines had business class seats I was able to buy for $2850. Guess which airline got my business? I need to make there same trip over the Xmas holiday and Delta/Korean Air fares are now in the $6000 range. I hope you find fares and a location for your vacation.