On all realms Non Ladder is the best spot to find the PVPer's

East has always been more populated. However, that doesn't mean quality.

West is less populated for the most part and usually more relaxed and casual.

East has more people and they take the game a lot more serious.

The game has slowed down as a whole. A lot more West players have changed realms than East players.

Which is why you may have noticed a slow down in the West trading grounds.