Because players with warband loot have the ability to attack any player the combat level of the current warband mechanics is RS gold nearly irrelevant. Legacy PKing is very weak in defense capabilities, which makes it difficult to defend. But, Jagex has plans to "revitalise" the wilderness, but no specifics have been provided. What are your plans to change your defense?
Where is the money coming from? While I'm not an economist, I believe it is fair to say that RuneScape is always subject to the effects of inflation. With the existence of the Grand Exchange the money a player spends is transferred to another player, and money that is gained often is earned by other players as well as monsters, quests and cheap OSRS gold so on.