So you would recommend signing up at 16, even if my personal odds of dying now are pretty small?
I haven't signed up myself yet, and I'm 28, so it would be suspicious if I recommended this. (My reasons for not doing so are somewhere between financial and "ugh, paperwork.") But I do recommend becoming actively involved in the cryonics specific subset of the transhumanism community and making long-term financial plans with this expense in mind.
What would you estimate as the probability of developing technology that will make cryonics work without a singularity?
I assign perhaps 65% likelihood to that, assuming we rule out long-range as well as short-range singularities, and assuming something like today's best cryonics quality levels. The added risk is because a) the ceiling for non-singularity tech might be lower (it sort of rule out matrioshka brain kind of stuff, if that is relevant), and b) non-singularity tech could take longer to reach high enough levels (even as compared to distant singularities) which increases storage-time associated risks. The latter kind can be mitigated to some degree by increasing storage security -- but it would have to be very close to arbitrarily low to survive for multiple thousands of years.
The likelihood of it working climbs to closer to 100% (or at least towards the chances of curing aging, which I think are in the high 90%'s in the long run, even without a singularity) if the cryostasis technology improves during our lifetimes, as the problems of cooling can then be resolved sooner and with less chance of being inherently unsolvable (for any given technological ceiling).
An exercise:
Name something that you do not do but should/wish you did/are told you ought, or that you do less than is normally recommended. (For instance, "exercise" or "eat vegetables".)
Make an exhaustive list of your sufficient conditions for avoiding this thing. (If you suspect that your list may be non-exhaustive, mention that in your comment.)
Precommit that: If someone comes up with a way to do the thing which doesn't have any of your listed problems, you will at least try it. It counts if you come up with this response yourself upon making your list.
(Based on: Is That Your True Rejection?)
Edit to add: Kindly stick to the spirit of the exercise; if you have no advice in line with the exercise, this is not the place to offer it. Do not drift into confrontational or abusive demands that people adjust their restrictions to suit your cached suggestion, and do not offer unsolicited other-optimizing.
To alleviate crowding, Armok_GoB has created a second thread for this challenge.