This comment may be like fingernails down a blackboard to many people here, but I'm going to say it anyway:

I think that, for almost all values of "you", you do more good by having children and bringing them up well than by expending resources to preserve and finally resurrect yourself. There's no reason why a generation of resurrected corpses should be in any way 'superior' to the generation of regular or enhanced human beings who would otherwise be eating their food and breathing their air. Likewise, if you've had profound ideas during your life, and you write them down, then others can pick them up later, with minds just as sharp and fresh as yours ever was.

As you imagine the human/posthuman population in the forthcoming centuries, why should it make the slightest difference whether any of those individuals have memories of being you?

It "feels" like cryonics gives you hope, but I think this "feeling" is rationally indefensible.

I will concede one small argument in favour of cryonics, which is that future generations will find those ancient corpses very interesting (especially if they can reanimate them, but perhaps even if they can't). However, I don't believe this is good enough reason for the 'average Joe' to freeze themselves. A billion frozen "average Joes" cost a thousand times as much to maintain as just a million, but are much less than a thousand times as interesting (especially if that million contains all of the "non-average Joes".)