Homes in Australia are always made up to the standards and the experts who work in this field are very well aware of the fact that all components are essential and we can improve and replace things with care without omitting the parts that are necessary.
So, sometimes we may see that every home owner has his or her own preferences and you may say that things may be different in homes. So the importance of components can be different. But these differences are not for basic things.
Like if the space is lesser than needed, everyone need space and creating space is one of the basic things which are required in renovation.
Though there are mirrors, lights, cabinets, sink and mixers that are always needed within the bathrooms. It is up to the client needs whether they need electric hot water systems or solar hot water. Any of the setup that is preferred may be considered as the basic and essential needs of any home.
The use of Poly pipe may be needed in most cases as it can be used in multiple conditions. So some are apparent components and some are hidden essentials which are not visible but are more important than other options we are using for improving the looks only.