Sorry to counter Chris G-Z, but we have risers at Walsingham and I recommend them. They enable a better view by all of the choirmaster's directtons and eye contact (not to mention a uniform view by all of the altar). Many churches have them, so I don't agree that they are essentially profane.
Most monasteries and Anglican churches will have the choir on either side of the chancel where there are two or three rows of choir stalls, each one higher than the one before it.
One can purchase individual padded kneelers - like a very very firm individual pillow. These work just fine at Walsingham. Our choir room is equipped with risers to mimic those in the church's choir gallery.
As for all this moving around, there should be none of this tolerated during the mass. Every one has a seat and should stay in it throughout mass, focused on the mass and one's role in it.
Also, to answer your next question - it is very good to have everyone together in the centre, or spaced out in a semi circle on either side of the organ. Your rehearsal and liturgy seating should have your choir in the same arrangement.
Sensible, rational people disagree with each other on occasion -- and sometimes, more than occasionally.
I'm glad we agree about the moving around.
Someone from SFdS in St. Louis can confirm my memory of the parish's choir loft... there were built in stairs, and chairs on those, but not risers. Whether these were brought in just for the Sacred Music weekend or not, I don't know.
I agree that it is important to have a helpful view of the altar.
The SFdS loft used to have risers (pre organ project). Currently, it has an extremely awkward layout that forces us to move around during Mass much like what Geremia described, but it has never been an issue.
To participate in the discussions on Catholic church music, sign in or register as a forum member, The forum is a project of the Church Music Association of America.