Should the government sell certain agencies, e.g. the Postal Service, AMTRAK, Smithsonian?

This is part of a government reorganization plan that I came up with. I can email it to anyone who wishes to view it.Should the government sell certain agencies, e.g. the Postal Service, AMTRAK, Smithsonian?
The Postal Service doesn't take any tax dollars. They depend upon revenues from their services.

The Smithsonian isn't a government agency. It's private, although chartered to serve the needs of the public. The government can't sell the Smithsonian or any of its holdings.

Amtrak is a corporation chartered by the US government to provide passenger rail service. The only reason it was established (by President Nixon) was that the private railroad companies didn't want the passenger trains--and they still don't. In short, nobody wants to buy Amtrak. If the private sector stepped up to operating passenger trains throughout the country, I feel sure that Amtrak would be sold (or at least turned into a completely private company).