Warning: mild spoiler for Daredevil TV show.
The third episode of The Defenders TV show on Netflix starts with
the resurrection of the Black Sky by the Hand
Shortly after, Alexandra has a discussion with this character (named X hereafter) that starts like this:
Alexandra: My name is Alexandra. You were born. You lived and died. And what you saw on the other side... the darkness, the absence of everything... it's horrifying, isn't it? I have seen it too. More than once. And all I want in this life is to never see it again.
(from Netflix's subtitles of the episodes)
What does the afterlife in Marvel look like?
Is there a Paradise and Hell? Do Asgardians go to Valhalla? Alexandra's speech seems to imply that there is nothing after death but she is completely evil, and had been using magic for a long time, and X is a kind of "the end justifies the means" character and had not been afraid to do bad things in the past, so it may be that this "nothingness" Alexandra is mentioning is a kind of Purgatory.
On the other hand, death is not definitive in comics, so what happens to dead people before they get resurrected?
Note that the question sprung from watching the Marvel Cinematic Universe, but I am interested in answers from the broad Marvel universe (comics, TV and movie universes alike).