Learn what mining actually does, why it is needed, and how the current solution works without centralized control.
Once you do that it is obvious why your idea makes no more sense than designing a toaster which also cures cancer and paints your house.

Unfortunately this is 100% correct, if it were that simple someone would of already done it & with the role that mining takes I don't see how it could ever be implemented but maybe someone smarter than me may one day have an idea on a different way to use POW.