There was a thread exactly like this in the past.
Basically, in short - Artemis is the most populated so if you like bumping into shoulders all the time as you walk around Varanas Central Plaza, then Artemis is a good idea.
If you like high population but you don't like it so overcrowded to the point where you don't have breathing space, Reni is also a great idea.
Govinda is also ok. Population is slightly lower than Reni's but still playable.
