Hi Dres,
The short answer is yes, if you only want to kite up to 23 knots.

If however, you want to partake in our slightly stronger winds, you will also need a 9m. if you want to go a bit further north, also throw in a 6m

In a true West Oz summer, you wont need the 16m as our winds are generally 15-25kn and frequently above 25kn.
See ya and good winds,