John , some good points.
I have always noticed the better singers have a balance more towards the vocals. I too think a more balance with instruments will make it sound more live. I also agree with using the strength of Ketron..Let us hear drums and bass.
This is also a weakness with great singers. Both Dave and Donny (great singers) do this

I will say sometimes the opposite is true too..A better player than singer will bury the voice too much..

Every time I watch a good jazz group, even with average vocals, the bass will stand out.. It is the drive in the group.