I sometimes wonder why people ask for chords to certain songs that I have only ever heard sung, very effectively, a cappella, the only "chords" being spontaneous harmonies from other voices, and I think, why on earth would you want to "instrumentalise" a song like that? And I have heard some of the results, which are pretty awful.

Having said that,for songs where accompaniment is more appropriate, I tend to prefer the "less is more" approach, maybe because of my own playing limitations. If I am writing a song,I will usually start with my first instrument (piano) but then have to think about what I can realistically translate it to playing on the eminently portable, but less proficient player of, guitar!