I was so lucky while working as I qualified for business class on trips to Europe and for first class on trips to Korea. At the time, round trip to the UK was about $6-7k and to Seoul was about $10k.
I recall my first trip to Korea. A domestic leg from the east coast to LAX connecting to an Asiana Airlines flight from LAX to Seoul. I was bushed even though it was a daytime flight and as soon as we were wheels up I tilted back and took a nap. Next thing that I knew I woke up and the flight attendant had taken off my shoes and stowed them under the seat in front of me and draped a light blanket over me. While Asiana's planes we nothing special they made up for it in service on that flight. Unfortunately, I didn't ever end up flying them again.
Similiarly, I had a great one-time experience on Virgin Atlantic from London to JFK. Again, the plane was ok, but they made up for it in service, including short head or neck massages while in flight. You would sign up before departure and the massuse would come to your seat and get you when she got to you on the list and bring you back to a seat and do the massage and then you woudl return to your seat. Pretty cool.