Been to Thailand many times over the past 12 years. Feel free to PM.
As you already have American I'd stick with it if your existing card is older than two years. If that's the case I'd do the two browser trick for 50k x2 and follow it up a few months later with a business card. That should pump your balance to 170k in short order.
I prefer Cathay Pacific business to Bangkok; an American OneWorld partner. You can find availability via BA.com
I'm currently working on a mid-March itinerary on Korean but it's only for the challenge of flushing those worthless SkyPesos.