Mining in World 1
You may think I'm crazy, but I'm not. Although I admit that World 1 is very good for trading, it can be used for other purposes as like mining as well.
Mining
You may be quite shocked to read this. But mining why? Let me tell you a fact about ore rocks. Ore rocks respawn time (the time it takes for a rock to have ore after mining it) depends heavily on the number of people in that world. The more people there are in a world, the faster rocks respawn. Jagex assumes that if there are more people in a world, more people are mining. This is not always true. In the case of World 1, the majority of people do trading and not mining. Thus, there will be less competition at the mining site for ores AND the ores respawn faster. Isn't it good?