If I were notch for one day, I would hire the makers of the Buildcraft, Industrialcraft, Equivalent Exchange(I love that mod to death ), Forestry, and tons of other amazing mods like that, and pay them to integrate their mods as a core part of the game. How awesome would that be? Also, I would hire a few more programmers/coders who's jobs would be solely to optimize the game. Then I would go on forums and image boards and actually LISTEN TO THE COMMUNITY, because we come up with some really simple, yet significant things that would improve the game!