I play bass for a children's choir which is usually 40-50 kids ages 6-15. The other regular musicians are a pianist, two violinists and an accordionist all 12-15 and a guitarist who's around 30. There is a conductor. How do you approach such gigs? To me it seems to be a balancing act between two goals. One is making it really obvious what the rhythm is and when the verses start so the kids sing loudly and with confidence. The other is making things sound a little more groovy, dynamic and interesting - the younger musicians just play their parts with not much in the way of expression, though the guitarist is very good at adding dynamics, color and a little ornamentation. The pianist is good but tends to play very stereotypical left-hand parts. I usually focus mainly on the first goal.