Non Diatonic Chords, always create interest and give the song that magic touch, Elton John is a master at using this device ,also Dianne Warren.

The same goes for trying family rhymes as opposed to done to death perfect rhyme.

Kurt Cobain used many non diatonic chords borrowing from minor scales an intergrating them with major chords.

Too many writers amateur’s write nothing but country that tells me their stuff will be precitable , generic and boring, (In general).