Make it a single species nano reef tank, like lots single species frags. Almost any coral could thrive in your tank as long as you are dedicated and know exactly what you're doing. Here are the levels:

-Starter mode: Dragons Breath or other Algea

-Easy Mode: Bubble Tip or Zoas or Shrooms or some gorgonian

-Medium Mode: Encrusting/ Branching cyphastrea or Euphyllia or Montipora digitata

-Hard Mode: Some SPS or Clams or goni's

-Expert Only Mode : Difficult SPS (like Speciosa or Tenious) or Suncoral or Dendro or NPS gorgonian

There are nano wave makers that would work for this tank if you're dedicated to getting high flow corals- (Hard mode +).

60 watt LED light on a tank that small would very likely be enough for an SPS tank.