We took DL ATL/ICN but had back-up plan for NRT.
Used frequent flyer miles to BKK on KE.

You can do the same route with ID's if you have full skyteam priv. Our last option was !D on Thai. We live CVG and have good seniority, so we got biz all DL legs and used 30K FF miles for biz RT each on Korean (which, BTW, was hardly "excellent" food/service/comfort)

Northwest would be good option as they have connect service thru NRT (unless you're trying during peak times)

We went end Oct and the weather was great, loads were decent and Airport Town by Incheon is easy in/out w/free hotel shuttles. We didn't have to overnight the first one but it was easier after 15 hr flight to sleep then take 7 hrs to BKK next day. We didn't want to get there all wiped out.

I don't know why BKK is "black hole for NR--there were so many carriers available. We had many options, but not all were reasonable on ID.