TG getting HND-SEA rights is going to be nearly impossible. What's wrong with NRT/ICN/KIX (especially the latter)?
Additionally, TG could also easily fly BKK-Europe-JFK/EWR if they chose the European connection point and the times well.
I would be very happy if I could fly TG F all the way to New York. It would be great if such a TATL route were introduced by TG.