I think you will find very few songs in the database (and in our history) that are racist in their essence. Those are the ones we have to be very careful about. There are many others that contain racist terms and concepts, but the songs themselves are not essentially racist - those are the ones we can salvage with a little doctoring-up.
We have to use a lot of good taste when we "doctor" a song. I think the way Art Thieme handled "Master of the Sheepfold" is a prime example. He did an excellent job, if I may say so.
Dealing with gender issues in songs is a newer problem, and fixing songs for gender problems can get really clumsy. The above example from "Mary Ellen Carter" isn't a glaring problem, so I think it can be left alone. "The Ways of Man" (Gordon Bok, 1977) and "Faith of Man" (Bill Staines, 1986) are absolutely wonderful songs written not very long ago, but it's a little "iffy" to perform them for certain audiences nowadays - I can't imagine how I could change them and still make them work.
I might give a word of advice on how to change wording to deal with gender issues - read the Bible. The New Revised Standard Version, completed in 1989, did a very nice, subtle job of removing masculine language from the 1952 Revised Standard Version.
-Joe Offer-