Since it's a "WIP" I'll hold off the nits until you declare it "done" or at least closer.

For now.... I like the progress to this point. The vox are a few db too loud. Adding BGV and HBGV will simply make it louder, so pull the vox down. You did mention that so you're aware of this issue. I don't know what DAW you use to mix final in, however, I use busses for the vocals.... that allows me to easily adjust the vox level in the song without messing with the balance between the vox tracks.

You're off to a good start.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.