Interserver BG/ARENA

Good afternoon!
Question to the project administrators!
I can't understand why Frostmourne, an interserver BG, was done on reality? Do you want to isolate the server PVE and BOP?
Online is sufficient for independent existence, but due to the imbalance of equipment, and for an unclear reason, the alliance with PVP realms is much higher! the horde faction, at least with me, has never won in 15 games. Why such a strange imbalance is not clear, is it possible to make a choice to turn on or off the server-to-server BG/arena?
Who agrees, support!
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