Please just consider adding NON-ESSENTIAL gold sinks. A static drain can theoretically work for the economy, but players are going to leave if they're saving up money for something and then they log in to find they're not even close to their goal. I don't mean to be harsh, but a static gold drain is such a grossly inelegant solution that you'll lose any respect for being a 'blizz-like' server. I know this server has exploded and it's doing something progressive and new, but you have to be careful making huge decisions like that. Laziness and losing sight of what is important (elegance) is what killed retail and the very same can happen to Lordaeron.
Gold sinks on the other hand are very simple. Instead of a lottery, just add things to the game that people can buy with gold. This is the Blizzard solution - you add a mount that costs something ridiculous like 100k gold or you add a service like transmog/void storage that is not at all essential to the game, but gives people a little reward in spending their gold. Consider an extremely expensive transmog, you'll know who is rich based on how fashionable they look. Players who don't have the gold for it aren't affected and those who do are almost certainly going to spend it on transmog (everyone will opt for that level of customization if they can and if they don't they're going to be hoarding gold regardless), but it's still a level of customization that is attainable in game and is nothing more than cosmetic. Mounts are another option, but as we see with retail, giving people with money (real or gold) mounts that are cosmetically on par with those that people spend weeks raiding/PvP for really kills the exclusiveness and achievement in that aspect. Sort of a "when everyone's a hero, no one is" deal which has become a primary turn off to the monster retail has become.