This is more... brainstorming then anything else, and the title is somewhat misleading. I really enjoyed Planescape: Torment, and I really like 4th edition. So, I was wondering: what elements of the party characters (Annah, Morte, Dak'kon, Fall-From-Grace, Ignus, Vhailor, Nordom) would need alteration to fit in to the cosmological changes caused by 4th edition?
For example, as a Githzerai, 4e Dak'kon would have hailed from the Elemental Chaos, where he and his fellows would have forced Shra'kt'lor-Drowning to form and stabilize from the upheaving elements around them. Fall-From-Grace, meanwhile, would have been born a Devil (or Baatezu) and while she could have still been sold to slavery, the idea of 'creativity to outwit tyranny' from her backstory doesn't quite work, as I see it.
The basic ideas still work- Dak'kon as one whose doubt caused the destruction of his city, Fall-From-Grace as a risen Fiend, Vhailor as an unquiet spirit held on by his fanatical devotion to justice, Nordom as a Modron who has gone rogue thanks to an experiment gone wrong, Morte as an escaped Petitioner from the Nine Hells, Annah as a Sigil Tiefling, Ignus as a mad wizard transformed into a living conduit for elemental fire... it's just that certain fine details don't work. What are these details, and how could they be tweaked to fit in with the way 4e has shaped the cosmos?
Why not tweak the 4e cosmos to better fit the Planescape setting, rather than vice versa? The 4e cosmos is a set of suggestions, really, and shouldn't be seen as a straightjacket to which everything has to conform, or a limit to your imagination. I appreciate that this is just an idle thought experiment (it's not as if Torment is ever actually going to be revised to fit the 4e paradigm), but it seems ugly to me.