The funds you have already will experience both income and growth – VHY is a high yield fund that will have lower growth, VAS is a simple Aussie index that will have both income and growth, and IVV a US index which will have mostly growth with a little income.

You could add more and more ETFs but you wouldn’t really be getting any different companies in it unless you look at emerging markets for example. But you already have the big building blocks of a portfolio for both growth and income, so there’s not much else to do. It would be just a matter of deciding how much of each you want and adding to it as much as you can.