Your post is a little confusing to me, so I will just tell you of my similar experience, you can draw from it as you see fit.
I had a bg band- 5 piece- guitar,guitar or harmonica (me, fwiw), upright bass, banjo, fiddle. often 4 or 5 part vocal harmony.
My son (darn good audio engineer, if I may say so, myself) came to Atlanta to record us. Set up project studio in my house. Recorded all instruments together, live setup. these mics (as I recall)
AT 4033
AT 4040
SM58, with pop screen, held in place between bass strings, below bridge, head resting against top of bass body.
SM57's close to each instrument.
All mics sent to separate tracks.
My guitar's piezo bridge pickup, to it's own track. (but not used on final mix down- not needed.)
SM58, set up at highest point of room ceiling, for room abiance.
Day 2: instruments recorded on day 1 played back, vocal tracks laid down on 5 new tracks, making a total of 12 tracks.
Later, my son mixed those 12 tracks to stereo demo. Came out sounding VERY good, with just enough, great natural reverb mixed in from condensers and/or room abiance mic (couldn't tell you how much of what, he did the remix, not me.)
Only problem we had was lead singer had to mouth the words and point to the line he/she was singing on a sheet so that everyone else could keep up. Even if singer sang as low as he could, it came thru, of course. For some now-forgotten reason, one song got done with singer (me) singing very low over instruments; it came thru on almost every mic track and messed up the final recording by having two not-quite-the-same lead vocal tracks; David (my son) could not totally eliminate the less-desirable one.
But it worked great, with that small exception. I would def. do it that way again- being able to feed off each other's energy was great. From a re-read of your post, I can say I now understand it- I think the way we did it will yield better results.
