Enabling alliances would be a huge mistake in this game more. The whole allure of 6mans was to get away from the mega-tribe lifestyle that official servers mandate. If alliances are enabled, official mega tribes/alliances will just create multiple 25 man tribes and rule multiple servers at a time. Conquest will turn into a worse official instead of an improved 6mans if alliances are enabled.
Please consider removing them, even if it means delaying the release of these servers.