As Ryszard commented, the song is well on it's way with the arrangement you have - remember if it is possible, you can play around with the bpms (if midi tracks) or sound stretch to speed up and slow down a few % to increase/decrease intensity as a substitute for emotion, then thin the arrangement at emotional times and lean in/out to the mic > closer more intimate, roughen your voice for "angst" at slower tempos.

It doesn't need more power - reminiscent of Billy Joe at first listen - see how he plays with arrangements. One of the best "emotional" "intimate" vocals I remember listening to growing up was Olivia Newton in "I Honestly Love You" - re-listen and see how she handled her voice. You've got good character in your voice - round noted and superb tremolo do not always a heartfelt performance make, Moo. Raw and unfinished can be good - bad notes not so.

This is good - I like it.

Ian
My "Original Tunes" Site
My gene pool needs more chlorine.