Do you intend to kill yourself when some or all of your current family dies?

No. I do expect to create a new family of my own between now and then, though. It is the prospect of spending any substantial amount of time with no beloved company that I dread, and I can easily imagine being so lonely that I'd want to kill myself. (Viva la extroversion.) I would consider signing up with a fiancé(e) or spouse to be an adequate substitute (or even signing up one or more of my offspring) but currently have no such person(s).

Actually, shortly after posting the grandparent, I decided that limiting myself to family members was dumb and asked a couple of friends about it. My best friend has to talk to her fiancé first and doesn't know when she'll get around to that, but was generally receptive. Another friend seems very on-board with the idea. I might consider buying my sister a plan if I can get her to explain why she doesn't like the idea (it might come down to finances; she's being weird and mumbly about it), although I'm not sure what the legal issues surrounding her minority are.

Edit: Got a slightly more coherent response from my sister when I asked her if she'd cooperate with a cryonics plan if I bought her one. Freezing her when she dies "sounds really, really stupid", and she's not interested in talking about her "imminent death" and asks me to "please stop pestering her about it". I linked her to this, and think that's probably all I can safely do for a while. =/