Why on earth would BKK be a hated destination? Surely would be one on everyone's ticklist to go to - it's a popular enough holiday destination so much have some attractions for downtime (ignoring the obvious of course).
LHR-BKK was never hated by crew.
BKK-LHR was however, because it was perfectly timed for people to jump on and get drunk. It was an 11am departure which then landed at 6pm UK time meaning an 11 hour day flight for the crew to manage - on old 777s. Added to that was the inevitable turbulence over the Bay of Bengal, and it's not hard to see why crew weren't keen.
Lagos & Accra are currently popular with some crew for the minimal jetlag (and the Lagos hotel is nice).
Newark is despised by crew as there's nothing to do around the hotel, while Miami is dull for crew who don't have an interest in shopping.
Tel Aviv isn't particularly enjoyed by crew as it's a short flight, with extremely demanding & difficult (imagine a safety video where the passengers do the opposite to the instruction they're given).
Singapore & Sydney aren't as popular as they once were as the 9 day trip doesn't really allow for a lot of free time.
As always, some crew pick the same destinations over & over again because they just like it.
M