Hi James,
It's not hard to see why this location is popular with photographers: a great beach, interesting piers and the potential for a great sunset every night must make it a good draw card for many a South Australian photographer.
Personally, I'm not easily seduced by sunsets; as the world revolves the sun is constantly rising and setting along a 40,000-kilometre swath of land and sea… and at any one time, thousands of people trying photograph this ongoing event. My usual feeling is that people are more seduced by the colours, not the content.
Despite all this, I still like what you have achieved this photograph.
Now… the one thing I would have changed with this photo was the position of the sun above those central posts. Had you moved the camera just the slightest amount to the right you would have positioned the sun above that central post and it would have been nicely framed overall. By moving to the right you would have also brought in more of that rock in the lower right foreground and this would create a more balanced a photograph too.
Now, you have used a moderately wide lens to make this photograph. Next time you go to this location, have a go at making the same photograph using a longer focal length. By doing this, you will make more of a feature of the piers on the horizon line. If you want to maintain the same area of foreground, all you will need to do is take yourself and the tripod backwards a few metres and you will achieve a similar result.
Good work,
Anthony