I wonder if in the Role Playing Games, they gave names to more of the aliens as they did in the Star Wars Universe.

There are certainly more on the map. I'd guess Trakis comes from one of the races on the far side of Centuari space, who probably regard the humans as being too far away and primitive compared with the Centauri to be worth coming to B5 for. The Lumati also fall into this
category, so this may be starting to change during the series.