'the money we have now' ie fiat currency, is manipulated in supply deliberately and openly to 'stimulate the economy' until eventually it gets all burnt out and then we have a crash, the big guys buy up the fire sale and the cycle repeats. It's a circle jerk. All you have to do is base the economy on money that is not centrally controlled. Then people can see clearly what the interest rate is really, and it regulates saving vs spending. High uncertainty = saving, low uncertainty = spending. The central banks manipulate it so it seems like the latter is always in play, until the last moment the pumping stops working and everyone scrambles for the exits.
Money is the only possible unit of measure in a market. But when its supply rate is controlled by certain groups, they can manipulate the rate to profit at everyone else's expense. Money controlled by one group for their own interests is not a money, but a debt instrument, one which they got governments to force you to use by various means. The beginning of fascism comes from banks controlling governments. This is how they pay for all the violence and this is why we can't have nice things.
It is nothing to do with the simple idea of a medium of exchange. This arises naturally out of barter. And it helps people regulate the economic activity by showing what is wanted and what is not.