Just a comment from a newbie sound guy with 30 years as a choir member: I don't want the choir in monitors as a singer.
The only possible use I can see is: If there is a large SATB choir with all members of each part standing together, AND there are sufficient monitor channels to isolate each part, then as A bass I want to hear the sopranos
. Or maybe the tenors, depending on the arrangement
. Never the altos, they are doing something different and if I get lost in their line down an octave the director
starts throwing things.........
Actually I want to hear exactly the same voices and accompaniment in performance that I hear in rehearsal. Churches large enough to worry about choir mics and monitors usually have a separate practice room, so putting voices in monitor that I don't hear in rehearsal is guaranteed to throw me off pitch.
So, this is an affirmation that choir members need to hear each other directly, not via monitors, or the music is going to suffer.