Taxpayer's choice. Give the taxpayer a direct choice of what they want to fund.
Mandate a percentage each taxpayer's income that has to be contributed.
Create a list of organizations (i.e. DoD, Welfare or General Fund) that the tax payer can elect to "donate" to.
This way the organizations have to prove to the taxpayer that they are worth the money. If the organization proves worthly taxpayers will directly fund its missions.
The taxpayer will be directly responsible for how their tax dollars are spent. Thus, providing the taxpayer with a sense of fulfillment in paying taxes and strengthening the necessary programs.
This choice system will save the taxpayers money by eliminating unnecessary programs and forcing the necessary to be more efficient.
Thank you for your consideration.