Personal identity is an illusion. It's often a useful illusion, but when you're dealing with something outside the normal usage, it can go way off. It results in asking meaningless questions like "Where did we come from?", "Where do we go when we die?", and "Is the guy who came out of the teleporter the real me, or just my clone?".

I don't mean to say that suggesting the existence of an afterlife is meaningless. I just mean that we're using a flawed model that implicitly assumes an afterlife, when there's no reason to believe in one. You assume that you continue to be conscious, when in fact there is a conscious entity at a given point in space and time, and there may or may not be another further ahead in time. You tried to be more skeptical about it, but you're still given it even odds. Since we live in an ordered universe, it's clear that almost all possible beings don't exist, or exist less in some sense or something like that. It's not even odds.

There may well be conscious beings beyond what we normally interact with. The issue here is that they aren't ex-humans. We know that a human brain is an integral part of the human mind. We know what individual pieces do. If there is some part of the human mind that survives death, it's not going to work the same way after we die. The mind might be modular enough that it can exist with some low-level animalistic intelligence, but more likely it would break down completely. It's also pretty unlikely that there is such a thing in the first place. There are a lot of problems that would be associated with an incorporeal organ. For example, how do you hold it in place?