Six In The Circuit?
My experience at YMMB is that Seven is about the most you can fit, That's one on the runway, one on climbout, one on crosswind, Two on Downwind, one on base and one on final. Even Six can be a handful.
All it then takes is One or Two very new students to stretch out their circuits and Two announced arrivals from Academy and GMH, perhaps requesting circuits on arrival, and the poor bloody controller can get very busy very quickly.
Add in some poor "Engrish" and one starts hearing things like "which Cessna are you? Waggle your wings" or "You will not orbit in the circuit unless I tell you to. Do you understand?". It's at that point, when I hear the controller beginning to struggle a little to maintain situational awareness, let alone myself, that I stop my own practice and make a full stop to get out of the way.
To be fair, this only seems to happen in the first few weeks of a major schools "New Intake", and after a while they get the hang of things, as we all had to, and life settles down until the next course starts.
What I'm going to try next time is asking for the Western circuit, which seems to be kept a little quieter and seems to take some of the arriving traffic from the East when there is not conflicting traffic arriving from Carrum or Brighton.
As for orbiting at waypoints, I'm assuming orbiting to the left (don't know the AIP reference), and people are going to have to have eyes in the back of their heads to make that work.