Be happy that people have died and sad that they remain alive (same qualifiers as before: person is not suffering so much that even nothingness is preferable, etc.) and the reverse for people who they don't like

Hmmm.

What is known is that people who go to the afterlife don't generally come back (or, at least, don't generally come back with their memories intact). Historical evidence strongly suggests that anyone who remains alive will eventually die... so remaining alive means you have more time to enjoy what is nice here before moving on.

So, I don't imagine this would be the case unless the afterlife is strongly known to be significantly better than here.

Want to kill people to benefit them (certainly, we could improve a lot of third world suffering by nuking places, if they have a bad life but a good afterlife. Note that the objection "their culture would die out" would not be true if there is an afterlife.)

Is it possible for people in the afterlife to have children? It may be that their culture will quickly run out of new members if they are all killed off. Again, though, this is only true if the afterlife is certain to be better than here.

In the case of people who oppose abortions because fetuses are people (which I expect overlaps highly with belief in life after death), be in favor of abortions if the fetus gets a good afterlife

Be less willing to kill their enemies the worse the enemy is

Both true if and only if the afterlife is known to be better.

Do extensive scientific research trying to figure out what life after death is like.

People have tried various experiments, like asking people who have undergone near-death experiences. However, there is very little data to work with and I know of no experiment that will actually give any sort of unambiguous result.

Genuinely think that having their child die is no worse than having their child move away to a place where the child cannot contact them

And where their child cannot contact anyone else who is still alive, either. Thrown into a strange and unfamiliar place with people who the parent knows nothing about. I can see that making parents nervous...

Drastically reduce how bad they think death is when making public policy decisions; there would be still some effect because death is separation and things that cause death also cause suffering, but we act as though causing death makes some policy uniquely bad and preventing it uniquely good

Exile is also generally considered uniquely bad; and since the dead have never been known to return, death is at the very least a form of exile that can never be revoked.

Not oppose suicide

...depends. Many people who believe in life after death also believe that suicide makes things very difficult for the victim there.

Support the death penalty as more humane than life imprisonment.

Again, this depends; if there is a Hell, then the death penalty kills a person without allowing him much of a chance to try to repent, and could therefore be seen as less humane than life imprisonment.