Yeah but I have done that by lowering my tax contribution too. In fact if I move into one of the new mega-super-skyscrapers that this will surely result in I may end up paying so little in taxes (because so many people will share the ground) that it won't be enough to pay for the police and fireservices, which surely will go up because it is more expensive and difficult to fight fires in so tall buildings.

So in effect I have shifted most of my tax-burden off to others, land will have very little value (because it will have to be taxed more and more heavily).

Of course you can mix it with older taxes, but then you have the problems you had with them too.