I thought Ken’s thank-you was essential.
I throws the audience into thinking he might need help going home and shows Ken’s world view to be utterly twisted by his Master’s teachings.
He genuinely find’s Han’s sacrifice to be ‘helpful’ and thanks him sincerly.
That’s really F&*ked Up! In a good way.That’s my issue: the only reason Kylo would say “Thank you” is because Han did something that was helpful. perfect line.
Han did help him. By putting himself in a perfect position to die Kylo has an opportunity to fully embrace the Dark Side. I see no issue with it.