I came across this video on developing the art of expressing thankfulness. There is power in thankfulness. Christians are encouraged to develop thankfulness in all situations. And I think its powerful to develop the art of writing a note, to express it.
Regarding the point on what to write as part of your valediction; I have got in the habit of signing off all my letters with “Blessings Craig B” Actually I tend to always end a conversation with people with “Bless you…”
Trinitarian Dance 