I am assuming you are talking about 30 vs. 300 when you are talking about stocking.
Almost anything would be appropriate assuming the tank is cycled.
A few shrimp i.e. cleaner shrimp would be fine, as is a six line wrasse. Six-line wrasses are quite pugnacious so you may wish to consider other tank mates carefully.
Percula or Ocellarius i.e True or False Percula's are fine for that sized tank. You may even consider getting captive bred clownfish from local members as well.
What kind of goby were you thinking of? Many gobies like Mandarin Dragonette or Watchman Goby do best with an established tank where the fauna and flora i.e. copepods are well established.
Xenia, Anthelia, Zoas, Gsp, Mushrooms are all good starter corals again assuming the water parameters are stable. Fwiw, zoas are preyed upon by Zoa Nudibranchs which do have feathery appendages. Asterina starfish tend to fine, but not all are. You may want to read up a bit more on starfish.
Remember stability is key, and patience is needed. I think when I first started I stocked my 30 40ish gallong tank (when I first started) with very inappropriate fish, and corals. Most if not all died in a very short period of time.