Good on you for cleaning up! Hopefully someone from the local council will see fisho's doing it one day, and stop locking us out of everywhere...
The rockwall - Is that the one to the right of it (when standing on land looking at the pier) that runs out into the water, or the one that runs along the edge of the water? There are some big flatties to be had off the one that goes out into the water. Go right out to the end. The one that runs along the edge (goes for ages around past the retirment village) has heaps of big bream hanging around it at high tide. Fish the last 2 hours of run in, and first 1-2 hours of run out.