I really don't see how anyone needs ops for map changes on it, the point of it is to play all of the maps in the pbcup rotation. Also, having everyone switch teams is a good way to change maps, since its like a vote, everyone has to be in on the decision, so there's nobody changing a map just because they don't like it even though others do.
I suggest it to have a short time for idle'd people to be moved to observer, this way nobody is AFK when others may be switching teams to get the map changed.