This sounds cool.
A good formation may be a stack of rows, progressing in an S formation. eg:
This would limit the height and depth however it could be done laterally so that we still have unlimited depth. The other advantage to a stacked formation is that it can be beheld from a single stationary view point, as well as limiting spread over chunks.
If we were to do a TOG formation, well, it would be awesome but nearly impossible without adding bridges and missing bits. It would also require a minimum of 22 sections/participants.
|... ... ...
| . . . . ..
| . ... ...
However if we did it as 3 sides of a rectangle it could make for a cool swinging camera view (perhaps requiring a track for in-game viewers), and also reduce the minimum number of sections filled to 18. It would also reduce the amount of bridging needed.
Just throwing it out there in case we want to make a TOG.
edit: lines added to T O G diagram so it formats properly.
edit: ok it's still not great but you get the picture.