Actually Tera made me think of this, and it applies more to that game (swtor would need to implement channels, but I think it kind of does already?), but since it has channels for each zone when they get full I don't understand why there is more than 1 "shard" of each type (pve pvp rp). With channels I don't see why they couldn't put everyone on the same shard and have the channels grow as needed. It would basically be like swtor or other games having a variable amount of servers and you could jump from one to another to play with friends. No more server transfers or merges to deal with and a much larger auction house/economy to fuel the players. The only downside would be much harder to get the character name you want, but with tera's optional periods that can help players out with names a bit.
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