I think descriptions are good to have, if the game goes the same "dialog box" way as Planescape: Torment, the Baldur's Gate games and Icewind Dale. Including it alongside dialogue also allows the same system to be used, later, for interaction with things that don't talk to you. Like, say, walls. It would also be useful when investigating a scene, for instance.
Regarding skills and their relevance, that really depends on the system that the game will be using, and so I think it's a little premature to elect a preference, as it will all be rather academic. A lot of players, including myself, will always pick the skills that give them the most options to talk with people, and I think that's a sound enough system.