In my opinion, there are a lot of great beginner fish. And bottom line, whether you are a beginner or expert, these fish are held in high regard:
Royal Gramma's stay a good size for a smaller tank. Afforable and hard to match the colors.
Clown fish are a great choice. I prefer to keep one only.
A dwarf angel after the tank matures. Flame, Coral beauty, Lemonpeel
Cardinal fish like the pajama or higher budget banggai
Hawkfish like the flame and longnose are fantastic fish with tons of personality.
Blennies like the midas and canary are real characters.
These are just some of my favorites. Stay away from triggers, tangs, lionfish and large angels because of the tank size and I would limit to four fish.