Thank you for the info. I hope it reaches the agent (and his manager) in question.
Nothing unusual was done at check-in (no strange seat juggling, op-ups etc), but the way he handled the check-in was just how I'd imagine a perfect check-in experience would be.
What was even nicer was that it wasn't even in the premium check-in section, and until he looked at my booking he didn't know that I was in F or GGL (I handed him my passport) but he handled the whole process like he was checking in a highly valued customer. I really loved that aspect of it, not in a DYKWIA way, but because it showed that he treated everyone with a real welcome, warmth, courtesy and helpfulness.