A couple nassarius snails and two or three others, like I have astrea and trochus snails. Some people suggest ceriths but I've never had them before.
You could add a small goby, court jesters are colorful, but other then that it will harder to handle with the bioload. Make sure you keep up with weekly pwc.
I have two ~1'' tomato clowns (I'm getting another tank in a couple months), one yellow watchman goby, one cleaner shrimp, one emerald crab, 3 blue leg hermits, 3 nassarius snails, two astreas and one trochus, o and a --- long candy cane pistol shrimp. Then corals. I do a ~30% pwc once a week and I have ~25-30lbs of lr.