There is a professional body for strata managers in Victoria – the SCA – but they are more inclined to protect the interests of their members than their members’ clients.
Consumer Affairs Victoria has a page on Owners Corporation Managers but they tend to be very loosely regulated.
And regarding the “favouritism” you will find that most strata managers will give some sort of preference to the people they think are going to be deciding whether or not they get their contract renewed. This is not corruption – it’s human nature.
Get on the committee and be a force for positive change. Just because there’s a brick wall, it doesn’t mean you have to bang your head off it.