I like cords and moleskin, but I kinda thing tweed trousers have a bit more charm and character, and being wool, generally preferable too. You can have both, but if I had to limit my wardrobe, I think I might well make do with no cotton trousers in it (not including jeans). Flannels, tweed, and cavalry twill, then some jeans for the extreme end, seem to cover most of the bases. Cords are the only thing that strike me as having a specific vibe to them that is not reproducable.
Dugdale cords are pretty good. The moleskin seem a bit uninteresting, though.