I believe that I do not want to be welcomed to anything by a robot. That is my ides of a form letter welcome is.
When I write a welcome letter I basically shoot from the hip, sort of speak. I write what I would want to here if I was in that position.
Of course there are some go guide lines in our training that are always best to go by.
You want to make the individual feel welcome, not like they were on an assembly line.