I had regular dialogs with Bob Lemke about adding variations, and did get several added with his help, including the 67 Mantle Punch Out variants
.
Also got him to add a 4th baseball item for the Topps 1954 baseball subset
I have not had any discussions about additions with the current editor, Tom Bartsch, but know others who have gotten such additions made through him.
Near the end of his tenure Bob Lemke developed a narrower definition of a variation and as a result removed some print defects that had been listed in the catalog. Mostly border breaks as I recall