Worship teams take on endless configurations depending on church size, stage size, vision and other considerations. If you use a full band, then you probably have a basic rhythm section of guitar, bass, keys and drums.
However, it gets more interesting when you start talking about singers. Your "singer structure" can vary, but probably falls into one of these categories:
1. "The Crowder" - In this structure the leader does all the singing except for the occasional shout out from one of the other band members. You can also chat back and forth with your band mate between songs "Letterman/Shaffer" style. If it's a guy leader, then all the dudes sing with him and the girls have to either screech out an octave above him or make something up on the fly. This is generally considered the coolest structure.
2. "The Tomlin" - In this structure the leader still does all the main singing, but there may be a back up singer of the opposite sex to sing harmonies and bring a balance of hormones to the platform. Praise team and choir people hate this structure. If you have 10 back up singers the rotation can get a little long.
3. "The United" - In this structure there are multiple lead singers who also sing back up and may or may not play an instrument. In this structure it's generally frowned upon for the keyboard player or the bass player to sing, and downright wrong if the drummer sings. It's also very favorable to have a hype man to wake everyone up on Sunday morning.
4. "The Walker" - In this structure there is one lead singer with a choir of back up singers. This is definitely higher maintenance than the "Crowder" or the "Tomlin" and will probably require a choir leader, someone to chart out vocal parts, and a wall to be knocked down in your worship center to make room for a choir loft. You'll need a sealed drum roomto isolate the choir mics or instead you could build a choir room out of plexiglass. It's also favorable to have a little R&B flavor in your music.
5. "The Kitchen Sink" - In this structure you will need the following: A 12 piece band, multiple lead singers with instruments, multiple lead singers without instruments, a choir, a praise team, a platform the size of an airplane hanger, a digital mixing board with unlimited virtual channels and an endorsement from Shure to purchase all your mics. Monitoring will be a logistical nightmare and in the end the sound man will only put half the band and singers into the main mix. Also, you'll have to rent a banquet hall for your worship team Christmas party.