In my *45* I have
1 black/white clown
1 Yellow watchman goby
2 firefish gobies
In 2-4 months I plan on adding a dwarf angel, mostly like a flame.
My tank is a softie/LPS reef, so I don't want all that many fish, and I like it being understocked compared to most people. I guess I just like the open swimming space for my fish with plenty of hiding spaces. The firefish and the clown all swim together, but if they wanted to, they would never have to see each other.