Since I still call Torment my favourite game of all times, I'd love something in that direction. I wouldn't take up the story of the Nameless One again, because as sad as that makes me, I feel it is complete already. A game with a similar feeling, and if possible with the Planescape setting, would be brilliant.
In my opinion, don't be afraid to
- be text-heavy. I still love all the reading in Torment.
- not have the characters speak every word of dialogue. I'm not a big fan of what Mass Effect has done to conversation systems.
Concerning the setting and roleplaying system, I don't know if it makes a difference when game licenses are concerned, but for me, the true planescape setting is still the one from D&D 2e. Third edition kinda screws it up.
Personally, I don't think it necessarily needs to be a D&D game - just use whatever works.
To sum up: Please give us Planescape. A world where faith can literally move mountains and anything is possible - lots of complexity for developers, but also lots of freedom. What's not to like?
All right then, who do I throw my money at?