Im not sure if mining is best way to earn money, but for sure it's waste of energy. I prefer trading. Well, there are already alt coins with emission mechanism tied to their supply. For example Nebula Network, which is not minned, but coins are generated due to distribution of cloud supply (in form of computational power and disc space). I thing it will be next step in cruptocurrency development...Time will see if Im right, but project is worth to follow.