This is a hard one to answer, because what I'd want also assumes privatisation of many industries, leaving the EU, liberalisation of many laws (thus reducing costs on defence), and cancelling of lots of other programmes, subsidies and welfares.
Assuming that I had my way on all of the above, and the Governmental debt was 0 or close (like, under 10% of GDP), then I would see no valid reason for an income tax at all. At any level. Also, low capital gains, inheritance and corporation taxes.







