Haven't really seen this suggested much, but I'd love to see account-wide banks available for players. This would be a separate storage space accessible by any of your characters, similar a Guild Bank but only for your account. You would be able to store Account-based items, so you can pass heirlooms and related items to characters on a different server/faction. You would not be able to send anything that is limited by servers, such as money or tradeable/sellable items. Primarily, this would be for Heirlooms, but it could also extend to special promotional items such as things gained through the TCG or possibly the black market auction hall that would be Bind on Account.