The single best compliment I had from a senior manager after emailing the findings of quite an arduous 2-month project early in my career was a one word email:

The single best compliment I had from a senior manager after emailing the findings of quite an arduous 2-month project early in my career was a one word email: "Good." Put me on cloud nine. I think it depends on who's doing the talking. Saying thanks more bring inflation to the term, leading to making up more terms when we really mean thanks.