Julia
I've encountered the same kind of challenge, only in a live sound circumstance. After I did a bunch of research and pestered people a whole lot, fooled with overhead chorus mics, multiple mics, and so forth, it came down to this combination for recording solo acoustic instruments, solo voice, piano, small ensembles, small choirs and the occasional 135 kid elementary school concert:
(2) Studio Projects B1s
(2) MXL 603s w/ shockmounts
(1) Studio Projects C3
A pile of mic booms.
VISA is now happy, I have a new pile of gear, and we'll see!
For a chorus, I'd have to have a really good reason to record more than two tracks at once, as I've come to believe that simpler is better. That choral recording is beautiful, though! Now I've got to brush up on x-y combinations...
I have yet to get experience with these mics, but I'm pretty excited about them; that combination is a wild bang for the buck.