To be fair Perth is a lot better than it used to be and the new chap in the tower has made a big difference, there are of course the odd few busy days where it gets a bit hairy.
I would suggest that the locally based pilots are actually mostly pretty good, its tends to be the visitors that dont follow the standard join that causes the problems.
IMHO pushing on into an active circuit without having the traffic visual is asking for trouble, the example from Sunday is a prime example of an accident waiting to happen.