I find most songs have one element that really makes the song. A bassline, vocal or big lead etc Some instrumentals are nothing without the vocal and at the same time some vocals are shallow and merely slapped on the instrumental. Also should depend on what most crowds identify a song for. For example i would never play the vocal version of calling or spaceman as those were added later by shitty rnb singers. Something like dont you worry child or sweet nothing would go down pretty poorly if you played the instrumental.