Well, it all depends on what kind of eel you want. Do you want small and docile that keep to themselves or do you want an aggressive outgoing eel that isnt always hiding and is often on the prowl for snacks?
The snowflake is very popular but I find mine to be kind wimpy. He hangs in the rock most of the day and can be intimidated by other fish. Even my 4 stripe damsels slap him in the face with their tails from time to time.
On the other hand, my BlackEdge eel is a terror. He is often on the prowl, kicking up live sand to make his burrow more comfortable and he is intimidated by nothing. He certainly isnt more menacing than a tessa or a green but he is very fun to watch and is quite the coversation piece.
There are many eel species and everyone has their own preferences so do some more research and pick one that most suits your needs.
Personally, this thread has me interested in the fimbriated and I might have to go get myself one.