You could easily get away with 4-5 smaller fish in there if you stock it right.
The goal is to find fish that stick to a certain part of the tank.
Yellow Watchman Gobies always stay in the sandbed and make burrows:
Blackcap Bassletts prefer to stay in and around the rockwork
Clowns can host a variety of corals. This guy hosted a Torch coral 24/7 and wasn't very active in the display:
A final fish could be a Bangaii Cardinal or a Red Firefish. Both are very colorful and prefer to hang out in the open parts of the tank.
Lot's of other options as well.
You could replace the YWG for a Jawfish.
You could do a semi-aggressive tank with Tomato or Marron Clowns and a Pseudochromis.
Your final fish could be a smaller flasher Wrasse like a McKosker Flasher Wrasse.
Just make sure to research your selections as best you can and be picky, it's a small tank and you will soon be full