Great songs? Or great singers?

I’m doing a Conway Twitty Musical called “It’s Only Make Believe” and it has been an eye opening experience to say the least. He had more than 50 number one songs and wrote many of them himself. I noticed that a lot of the songs got to be unique to him as time went on. By that I mean only he could really sing it and make it work that well. They expressed his personality. One song I’m thinking of is “Don’t Take it Åway”. There’s a line in there that says, “I hope I don’t embarrass you here in front of your friends” as he’s trying to win her back. The girls love this line. I don’t care if George Straight sang it... it wouldn’t work as well as it does with our spot-on Conway impersonator. So maybe writing a great song is more about expressing a certain personality or character just right...how would HE tell this story? WOULD he tell this story? What story WOULD he tell and how? Then maybe some artist will hear that come out in your song and decide if it expresses some part of himself too. Enough to put on his record? Maybe.