Again, this doesn't give the government any more power than it already has. If they want your home, they will seize it.

Arguing that the government needs to jump through hoops is some sort of defence to you isn't relevant. They can and do jump through those hoops all the time, and home-owners are left with assessed values that certainly don't reflect the value of the home to them.

In the Greek system, the home-owner can arbitrarily decide what their home means to them, by assigning a value to it themselves. I'm not sure how you take this to mean that the government will suddenly decide to buy up undervalued homes throughout the city. That doesn't make any sense. The government is not a real estate firm, and there is no benefit to them or the taxpayers to saddle themselves with property instead of taking a short of a few hundred dollars, which they will more than make up from people who do value their homes. They'll continue to act as they always have, Rezoning and developing as they see fit. In this case however, people will be offered fair value for their homes - fair, because they've priced the house themselves.

So to answer you question, if your house is truly worth so much to you that you would be crushed if the government decided to build a highway where you live, yes, you do price it a 200% (and pay the taxes as such). The Greek system gives you this choice. Under current North American systems, you'll get the assessed value and be told to bugger off. If you're really lucky this will happen during a recession when your assessed value is lower and most construction projects occur. If you're really, really lucky they'll build something next to your lot, force you to take them to court, then offer to settle at the new, post development assessed price.

The Greek system wins in my mind in all cases where a government would look to seize property from an owner.