I can recall doing Dylan's "North Country". Loved the song. (Yes, I'm aware it is not the traditional song on which he based HIS song.) After a while I went

(G modal) If you're travelling in the (F add G) north country (G modal) fair
(C) Where the winds hit (G modal) heavy on the (C) border (D) line, etc.

Got so I liked doing the song that way and it worked for me. It didn't 'hurt' the song in any manner. That is the key for me. Stay true to the intent of the writer, and if a few things get changed along the way, welcome to the 'folk tradition'. However, I have great respect for traditional tunes/words, and I have done some where I stay with the original all the way. I have never changed a song just to change it.

A fellow recorded a song I wrote more years ago than I care to think about. He changed a few things. Frankly, I prefer what he did to what I did.

Some things on Earth have to remain Holy. Barbara Ann (by the Beach Boys) is one of those things. I was aghast to see that some Madison Avenue type had taken the song and changed the words so's to sell Barbeque Sauce. That was disgusting. Change just to change things doesn't mean it's a step 'up'.