My choir does every 4th Sunday, so we repeat the Introit every 4th Sunday for 6 months. Since it's a month between when they hear it, the congregation doesn't seem to mind. The last 3 rotations we did
- God Is Here - Martha Munizzi
- Enter In - Joe Pace & Colorado Mass
- Praises - Jason Nelson
Since we like for our Introits to be short, we only do the first verse or two and/or a few refrains of the chorus, then we bring the song back and complete it for the Offeratory. We pick fairly simple songs, since we've gotten into the habit of having my kids on the instruments.
June is the last time we'll do "Praises". Starting in July, we'll do "Welcome Into This Place" - Joe Pace & Colorado Mass
I guess what makes a good opening depends on what you are trying to do with the opening. In our case, we want to set a fairly passive, reflective, open mood. If you want to set a high energy, upbeat and involved mood you could go with "We're Blessed (Blessed In The City)" or "Friend of God" or "You Are Good". We tend to save the high energy numbers to the selection just before the pastor delivers the sermon.
