From what I see, your questions completely ignore the crucial problem of weirdness signaling. Your question (1) should also assume that these hospitals are perceived by the general population, as well as the overwhelming majority of scientists and intellectuals, as a weird crazy cult that gives off a distinctly odd, creepy, and immoral vibe -- and by accepting the treatment, you also subscribe to a lifelong affiliation with this cult, with all its negative consequences for your relations with people. (Hopefully unnecessary disclaimer for careless readers: I am not arguing that this perception is accurate, but merely that it is an accurate description of the views presently held by people.)

As for question (3), the trouble with such arguments is that they work the other way around too. If you claim that the future "me" 20 years from now doesn't have any more special claim to my identity than whatever comes out of cryonics in more distant future, this can be used to argue that I should start identifying with the latter -- but it can also be used to argue that I should stop identifying with the former, and simply stop caring about what happens to "me" 20 years, or one year, or a day, or even a minute from now. To which I can respond that yes, there is no rational reason to care about the fate of the future "me," but I just happen to be a sort of creature that gets upset when the future "me" is threatened and constantly gets overcome with an irresistible urge to work against such threats at the present moment -- but this urge doesn't extend to the post-cryonics "me," so I'm rationally indifferent in that case.

If you believe that this conclusion is false, how exactly would you counter it? (This objection obviously has implications for your question (6) too.)