Well, since "improve" is a relative and a matter of taste, it is impossible to improve a language, isn't it? Make it run faster, and it will either take up more memory or be slower to develop with. Make it faster to develop with, and it will run slower or have some other tradeoff.

Hence, "use the right tool for the job". And when your focus shifts from "quickly building a product" or "quickly adding new features" to "rock-solid stable and fast", then you need to switch tools. Simple as that.