I think that great poetry is the most interesting and complex use of the poet's language at that point in history and so it's even more exciting when you read a poet like Yeats almost 100 years old now and you think that perhaps no one can really top that.
Any kind of anthemic song for the most part they're on the positive side of things. It's not hard to identify when a melody is just one degree too complicated or one degree too simple and where that line of pop memorability lies.
