I agree, but given that benefits (excluding disability benefits) are set at the minimum level the government and its advising bodies believe is needed to cover very basic needs like food and shelter, we cannot do this by lowering benefits, not unless we want people starving to death or living on the streets.
We need to raise the minimum wage, which would also help spread the tax burden. Raising the NMW will also push up middle incomes because who's going to spend years training to be a nurse or teacher and gaining student debt when they can work in a shop for more money? This means those at the bottom and middle will be paying more tax and taking less from the system.
And I know businesses will fold, billionaires will have tantrums and move to Dubai, a tin of beans will cost £999, etc, except none of this happens in other countries with higher wages and standards of living, so what are they doing that is different and why can we not copy that?