Define best written. I know you mean lyrics, but I mean there are a lot of different type of categories you could look at a song being the best written. You could view the lyrics like a poem. Or it could be a popular song that a lot of people can relate to or something that is your favorite.

If I were going to look at songs like poems and also keeping in mind what artists and genre I like... I'd probably choose:

"Barnacles" by Ugly Casanova or "Third Planet" by Modest Mouse (both the same songwriter, Isaac Brock.