I like to play Spain. The main reason for me is that their special ability lets them pursue basically any type of victory. It is in my opinion one of the most versatile and flexible nations depending on what starting buildings you get. That extra scout, movement speed, and navigation allows for a very fast expand, and quick city building which can be used for every strategy.
Edit: But I still think that the arabs are a bit too good for going after culture and researching pottery first.
Off topic, but now I feel like we're the only group who actually randomizes the civilizations o_O And we never had the Arabs, yet...
We play with a random draw, with the caveat that if you draw a civilization you have played before (because we don't get to play often, no-one in our group has yet played every civ), you can re-draw once if you wish.