Using Series Column for Genre?

I currently have a separate genre column, before series. I am thinking of merging the two columns to save screen space.

I don't know how to merge columns, though, and don't want to overwrite the series info for books/articles which have series info, but I do want to save space.

I have tweaked "auto increment series index" so it doesn't try ordering the books; it used to mis-order them.

Has this worked for anyone else?