Besides I mentioned earlier. If you are not happy with your security service provider (Govt) why should you have to move hundreds or thousands of miles, give up your job, your local community etc and go into an uncertain situation when you could have a situation where it is as simple as changing your telephone provider or ISP? It just doesn't make any sense.
I talk about what already works now if you are not happy with the state you happen to live in. You, instead, are trying to sell a pig in a poke, something which is simply not here today and probably will never be.
The point is that you and I should not support the use of force to compel people to have just one government in an area. It's as immoral for governments to claim a monopoly in an area over defense and law and order as it is for the mafia to have territory and force everyone within it to pay protection money.
When your neighbor says he wants to secede, you shouldn't be among the ones opposing him. Nor should you reply by saying it is impractical. He has that right, and it should be respected. Nor should you reply by telling him he'll have to move. That's just wrong - he and everybody else should have the right to secede, collaborate together to form new governments (rights-protecting institutions), or whatever they want, as long as they are not violating anyone else's rights.
Though I didn't expect that you would like this alternative, which was pretty clear right from the start
The problem with your alternative is that it's immoral to make that the only choice.