The single largest motivation for me is just that a future which is powerful enough, and rich enough, and benevolent enough to revive cryonicists is likely to be a very pleasant place to be in. If nothing else, lots of their everyday devices are likely to look like marvelous toys from my point of view. The combination of that with the likelihood that if they can repair me at all, I'd guess that they would use a youthful body (physical or simulated) as a model is quite enough to be an attractive prospect.