John, I am a little surprised you haven't gotten any replies to this topic, but perhaps your post said enough ...

I might add that when playing an instrumental, even if it is part of what might primarily be a vocal performance, play it as if you were singing it, that is, not note for note, beat for beat ... I also find that some performers who are - or were - primarily instrumentalists - often sing a song note for note, beat for beat ... as you stated, FEEL the song ...

A while back I posted "Through the Years" and received very positive response on this board, especially from a member who was going through a rough patch at the time ... I think what contributed to my performance of that song was the fact that we also were - and are - going through a rough patch with a family member who is a great part of our lives ...
In essence, it is the emotion - happy, sad, whimsical, whatever - behind the lyrics or melody that makes the performance ... have a sense for what it means, and get your audience to feel it as well, and you will have a successful performance ...