A new form of government

After my last post I thought I'd post this.
A while ago I came up with an idea for the full devolution of democracy, using online voting to the n'th degree. Based as much as possible on various voting/communal online systems. I'm not saying it's without flaws, but I present it here for comment and improvement.

The basic idea goes that everyone has the vote on every single subject.
But i hear you cry, this would be crazy, for a start there'd be too many decisions every person to make.
Correct. That's why you can appoint proxies.
For example if the subject to be voted upon concerned agricultural policy, and your mate Hugh nicely summed up your views on the subject, or at least summed them up enough that you trusted his views then you'd let him vote on your behalf for all fishing related things.
Let's say you met this guy Jeremy down the pub and you liked his ideas on the transport system, you could delegate your transport related votes to him.

So a bill gets proposed in true online democratic fashion (how this happens I'll get back to) and people tag it with tags in order to categorise it according to the various categories. Agriculture, Transport, Education, etc. Obviously most things would have several tags and therefore there would be conflict. This would therefore need you to have an arbiter in case of conflict. Depending on how important the subject was (determined by the amount of acticity on that topic) you would then either delegate it again (perhaps to the equivalent of your MP) or make the resolution yourself.
Ah, but how would the bill get proposed. Simple people could vote bills up or down. If your delegate chose to vote a bill up or down that was within his delegation remit then he would vote it up with the force of all the votes he had control over.

Now there are a number of issues with this system, not least the common problem of people voting for more public spending and lower taxes. There'd be so many on the dole voting for more taxes on the rich that the economy would probably collapse. Given every bill would have an economic impact and assessing the impact of this would be none trivial then how do you even assess the cost of each proposal never mind balance the budget.
My idea, (although it too is flawed) the personal tax allocation. You buy into government services. For example you can vote up or vote down the spending on military, but the cost is shared equally between all taxpayers. You can vote for more or less money spent on roads or whatever but you must pay your appropriate share. Two problems with this, how do you decide what is fair and how do you prevent the race for the bottom.
Simple, when it comes to tax we formalise the agreement that already exists through lobbyists and bribes, he who pays the piper calls the tune - sort of: on a logarithmic scale the more tax you pay the more say you have in financial matters. That is when it comes to tax policy it costs you (at least) four times as much to buy twice the votes. If you as a rich man vote for yourself to pay less tax, you then have fewer votes with which to maintain your position.

As I say it's far from perfect, but it's certainly different from our current scheme.