Solution to "Lowering the Gold" issue.
Waging war costs money right? In order to fasten up content releasing NPC's should accept in-game donations.
We should copy Blizzard and create an NPC that accepts "bare gold" or even better, "supplies" such as frostweave cloth for example, which people would buy from AH for their gold, and even keep the global economy running healthy while supporting the joint cause.
Guilds who have donated most to the NPC's will be listed by all NPC's or in some billboard. this creates competitive environment between guild of horde and alliance. The superior guild is obviously that who has most funds to spend into "Horde - Alliance joint operation front" against Lich king (for example). and everyone could see whos the one who made it possible to raid that place say, a week earlier. You could even have billboard for individual players.
i.e: Guild <Example> has provided total of 13200 Frostweave clothes | and/or | 50 000 Gold coins for the joint operation against <enemy>, and thus enabled us to start the operation <x amount of days/hours earlier>.
As for devs, when you announce new content, just add <x amount of days> onto the release date which will be reduced by the efforts of above "event". This way you'll create the "need" to spend gold/items in game and at the same time offer the players ability to affect into the gameworld.