Figuring out vocal levels

IMO, Every word should be audible, but the vocal should not overpower everything else. It's a really tough balance. However, keep in mind that the "right" vocal level depends on how well it serves the song. It is also a very subjective thing. Instead of focusing on levels alone, think about carving "space" for the vocal using a combination of EQ, panning and reverb/delay.
 
Regards,
Dan

Lovely John Martyn vibe on this song. Thought I was listening to ''..And'' for a sec. Following that comparison, I think the vocal sits really well, it's more of an instrument/texture than a lead vocal, just the way JM used his voice in his latter years.
 
Reminded me of this track;
 

Here are the steps I take in order to get vocals sitting at an even level and at the right level for the music.
 
Before I mix I edit the vocals in a separate editor.  I run a VU rms meter over the vocal the whole time during editing.  Once a reference level is chosen eg 0 dB VU = -14 or -20 dB FS the vocal phrases can be checked for consistent reaching the 0 dB VU mark.  You are off to a good start getting a nice even vocal level before any compression is applied.  And when it is, it can be a low ratio and not severe. The rest of the vocal chain is up to you but if the voice and the recording is very good it can be cool how little processing can be applied for a great sound.
 
The leveling of this vocal level is important because once you get the next step of sitting the vocals nice into the music you want it to stay there.
 
That just leaves balancing vocals to the music.  I do this on a small mono Auratone type speaker being fed a L + R mix at lowish volume eg 70 dB SPL or under. I sit close to it about 6 to 8" away from it looking directly at it.  This is better, clear and more accurate than standing outside the door of your own control room with the speakers playing louder inside.  (In a nice way it is simulating the same effect)  Get the music sitting nicely and then ease the vocal in.  There is a point where they are clear and well balanced.  Also when the vocals are right they don't alter the overall movement of a VU meter much over a whole mix.
 
The John Martyn track passes the small mono speaker test with flying colours.  They are sitting real nice against the music.  They do drop down at some point later into the music a little but that is a very intended effect.  Most of the time the vocals are sitting right and riding the crest of the total wave nestled in with the music but also just slightly above the music.  All of this is more pronounced at low volume on a small speaker.  It works every time.  When you crank up on your big speakers the vocals are just in that perfect stellar position.
 
Then comes the all important job of turning the reverb level now down to half!
 
Note: The vocal reverb appears quieter on the small speaker at low volume.  This is one time up loud on your mains is great because you will hear the vocal reverb big time. And it should make you want to turn it down too.