Wow, these are expensive. Horribly expensive. TK to BKK you should be able to get for 1/2 that price or less!

TK can be great, but you need to look a the aircraft type and avoid the 777s and probably also the 330s. The 359s and 789s are good.

NH has a great product JFK-HND. HND-BKK - just o.k. At these prices I would check what NH First costs ...