4 servers is already too much as it is, and now you would suggest an additional 3?
You realize servers cost money, right? A server like Zeth'Kur with a median of 600 people online is NOT paying for itself, on the contrary, players from Anathema, Darrowshire+Elysium are paying the costs of Zeth'kur everytime they donate; your suggestion only increases the burden players from the other 3 servers would have to take in order to maintain 3 additional dead servers.