From what I've seen and from what's been explained on the board, I thought the way it works is it transmits the voice messages in the order they get to the system, pretty much exactly like what you are asking for here.
If 6 people key their mike to say something on range while someone else is talking on range, it sends their messages in the order they're received, doesn't it?
Now, are you talking about making it do that regardless of what channel is transmitting, so that if someone on range says something and someone on vox says something at the same time, it queues them like it does one channel? I think I've seen tuned vox and range vox stepping on one another. If so, that would be a worthwhile addition.
Wiley.