Well, I would significantly reduce some taxes - in fact most of the ones you list will be nullified (NI, fuel duty, import duties), and the others (VAT, capital gains), significantly reduced.

I think the problem with sticking with just one tax and keeping it high (so, if it turns out that the typical person loses 50% to tax, so kill all other taxes and just have a one lump sum tax of 50%), is that it will unfairly tax some people (it assumes £2,000 collected a year in fuel duty, typical - how is that fair on people who don't drive, for example?). Once you start means testing, and allowing for changes based on what people do and don't do, then there Inland Revenue costs will start climbing again.

That is the key thing, yes. I believe (and can't prove) that the differences in lifestyle would cancel out for nearly everyone, and the benefit of making tax simpler and harder to avoid would be far greater. So no allowing for changes would be needed.

I don't believe it is the function of government to be encouraging and discouraging specific behaviour (fuel use, importing, varying VAT on items) with taxes. The market-set price should, under capitalism, be the actual price.

Everyone should pay the same % of their wages without any tax breaks of any kind.

Well, I'll leave the first paragraph, for now, as I haven't really put much thought into the idea.

The issue I have with the second paragraph is that the market price seldom reflects the actual costs. Petrol prices without fuel duty, for example, doesn't reflect pollution, noise costs, congestion, blah, blah, blah - I also believe that fuel duty doesn't reflect this particularly well, either, and so I propose another system where both fuel and road taxes are scrapped in favour of a more complex version of the congestion zone.

Yes. I 100% agree there, not as a tax issue but as an environmental one. The money gained should be ring-fenced to mitgate the harm though. I'd quite like to see things charged according to whether the activity is sustainable.

same as everyone

Just because someone makes more money than another doesnt mean they should pay more taxes. Everyone who lives in the US should pay the same tax %.

I wrote an essay on it, a while ago: https://docs.google.com/View?id=dgbq53jw_26fb7rm7fz

Disregard my solution, though, it's fucking awful. A system using number plate recognition technology would be far more elegant/easy to implement (as they currently do in London)

If i could set the rules, there would be universal salary caps, and any income above that had to be given in the form of stock in the company you work for, frozen in your possession for at least two years, to guarantee that incomes above a certain level were 100% dedicated to productive investment, though the ceiling for that would be at like $10 million annually.

Also provisions to seize 100% of income that people deliberately attempt to hide from taxes

Duh.

Same as everyone of course.