Common Christian Objections: (Guesses, as I am no longer a Christian) and rebuttals (Within the Christian religious framework, as it's not always feasible to convince them to be Atheists).
1.) You're trying to get something that's forbidden. (Life is important, so God must control it, if you were supposed to have more, you would already have more. Therefore trying to get more should be viewed as bucking a limitation.)
Rebuttal: If you attribute other medical breakthroughs to God, how do we know God didn't give this to us, too?
2.) Only God should decide when you die. (He forbids you from living longer except at his discretion.)
Rebuttal: Why should I believe that a loving God expects me to just shut up and die?
3.) You're making a deal with the devil. (Because only God should decide.)
Rebuttal: Nobody asked me for my soul or to do anything evil to sign up for cryo. The ten commandments don't tell me not to. In fact "You shall not murder." may be interpreted as an obligation to continue your own life wherever possible, otherwise you're knowingly choosing to die when it isn't necessary, thereby "murdering" yourself. I see no evidence that this is temptation by the devil.
4.) You're tinkering with the sacred.
Rebuttal: If life is sacred, and saving lives is an option, isn't it worse to fail to do everything you can to save lives, even if your attempts are somewhere between not perfect and horribly incompetent at first?
I heard that women are difficult to convince when it comes to signing up for cryo. In mentioning cryonics to a dying person, there seems to be a consensus that it's not going to happen. I encountered a post: Years saved: Cryonics vs VillageReach, which addressed my main objection (that the amount of money spent on cryo may be better spent on saving starving children, especially considering that you could save multiple children for that amount of money with high probability whereas you save only one life with low probability by paying for cryo). Now I'm open to being persuaded.
My first instinct was to go read a lot about cryo, but it dawned on me that there are a lot of people here who will want to convince family members, some of them female, to sign up - and these people may appreciate the opportunity to practice on somebody. It has been argued that "Brilliant and creative minds have explored the argument territory quite thoroughly." but if we already know all of the objections and have working rebuttals for each, why is it still thought of as extra difficult to get through to women? If there were a solution to this, it would not be seen as difficult. There must be something that pro-cryo people need for persuading women that they either haven't figured out or aren't good enough at yet.
So, I decided to offer myself for experiments in attempting to convince a woman to sign up for cryo and took a poll in an open thread to see whether there was interest. I don't claim to be perfectly representative of the female population, but I assume that I will have at least some objections in common with them and that persuading me would still be good practice for anyone planning to convince family members in the future. Having a study on persuading women would be more scientific but how do you come up with hypotheses to test for such a study if you have no actual experience persuading women?
So, here is your opportunity to try whatever methods of persuasion you feel like with no guilt, explore my full list of objections without worrying about it being socially awkward, (I will even share cached religious thoughts, as annoyed as I am that I still have them.), and I will document as many of my impressions and objections as I can before I forget them.
I am putting each objection / impression into a new comment for organization. Also, I have decided to avoid reading anything further on cryo, until/unless it is suggested by one of my persuaders.
Well, have fun getting inside my head.