I'm still working on a way to offer uploads to the community, sorry about that. I attached the image you emailed me to your response above.
I still need to work on an article about this, but here is what I typically recommend:
Camera 1: Wide shot (can also be referred to as a "bail out shot"). This is your main establishing shot of the room. It is usually right in the middle, or heart, of the room (like you have in your diagram) and gives you the views that someone would see if they were sitting in the room.
Camera 2: Tight follow shot. This is usually right next to Camera 1 and does all of the tighter shots that will be used a majority of the time (tight of worship leaders, tight of pastors, etc.). It is typically placed as close to Camera 1 as possible to keep cuts between the two consistent and least distracting.
Cameras 3+: These are the side angles, handhelds, and any other additional cameras you wish to add. These are typically where the creativity and fun begins, while cameras 1 and 2 are more for coverage of the critical (and standard) shots.
Now, with that context, I'm curious how you see cameras 1 and 4 working together? The two issues I see right now are 1) Camera 1 will be right in the middle of Camera 4's shot all the time, and 2) using a slider from 80' is probably not going to give you the movement you expect, at least not unless the slider is 20 ft long. Part of what makes sliders work is the parallax effect, where foreground and background elements move dramatically. This can only be accomplished from 80' away if you a) have a ton of lateral movement, or b) have a lot of people in the near foreground of the shot, like a foot or two from the camera lens.
Once you get to a place where you're confident in your camera placements, then you can choose the best lenses for those situations.