"Better die and spawn a ghost, than die and leave nothing." What's the point of a ghost? How does this make your situation "better"? Your point is based on the assumption that death is inherently "bad".
Ceasing to exist is, in a strict Darwinian sense, bad. Reproduction and, to an extent, continued existence are good.
I say the immortality of my genes pale in comparison to the immortality of my thought processes. Even if the copy isn't really "me", it will have the same influence I could have had if it was. I may have other goals besides not dying. My ghost would have at least a chance of carrying them out.
Hell, yes. And it is not an assumption, it is an observation.