I'm not sure that's a universal feeling. I would certainly would put it the other way around.
What are your exact (or, I suppose, approximated) probabilities? Maybe I don't have a good sense of this.
Many human moral systems allow one to kill others to save a life.
Well yes. This brings up a whole host of issues though. The best analogy to the point I'd like to make would be abortion. Similar to fetuses, human moral systems do not view corpsicles as "lives". Which is why those moral systems you mentioned wouldn't approve of murdering someone to save a corpsicle, just as it would be widely considered "wrong" to shoot an abortion doctor. Whether or not it actually is wrong is not my point, but only that you can't adopt the "many human moral systems allow this" argument without paying any attention to the fact that human moral systems wouldn't see it as a life anyway.
In the same vein, I don't think your decision theory argument pans out either, because following the rule "kill people who are trying to murder corpsicles" doesn't equate to "kill people who are murdering other people" in the view of, for all intents and purposes, everyone, and ergo doesn't have the intended deterrent effect. In fact, the effect it would have would be to get you jailed, a newspaper story about the "crazy transhumanist who shot someone to save a corpsicle", and, well, the corpsicle will just be killed anyway once you're imprisoned.
What are your exact (or, I suppose, approximated) probabilities
I'd estimate around a 5% chance for cryonics to work in some form, and a 1% chance of a Singularity-type event, broadly construed, in the next 40 years.
The best analogy to the point I'd like to make would be abortion. Similar to fetuses, human moral systems do not view corpsicles as "lives".
Huh? Many moral systems do see fetuses as lives. That's part of why abortion is so controversial. Moreover, what matters is not whether those systems normally see cryonics patients as aliv...
Check out the latest episode of Castle (Headcase) to see Cryonics covered in mainstream fiction in a not entirely terrible manner. The details are not exactly accurate but probably not more inaccurate than similar fictionalised coverage of most other industries. In fact there is one obvious implementation difference that the company in Castle uses which is how things clearly ought to be:
Amulets of Immortality
It is not uncommon for cryonics enthusiasts to make 'immortality' jokes about their ALCOR necklaces but the equivalent on the show make the obvious practical next step. The patients have heart rate monitors with GPS signalers that signal the cryonics company as soon as the patient flatlines. This is just obviously the way things should be and it is regrettable that the market is not yet broad enough for 'obvious' to have been translated into common practice.
Other things to watch out for: