I feel for you, and a lot of the problem must be local connections as here are my tests from Christchurch 8:20am NZ Local time
Brisbane 76/84 (Voda) 58 ping
Sydney 57/80 (Telstra) 156 ping
Melbourne 47/81 (Telstra) 147 ping
It was the same here in NZ, anyone can upgrade core components or shape...