Well, you've got me there. I've never paid as much attention to how the camera looks as I have to the pictures that come out of it. So on that end, if you're looking for a more pleasing appearance in a camera, I'm not too certain that anyone can help you other than yourself. Also: As far as I know, none of 1-series have a grip battery like the 5D. The battery is internal where the grip would be, and that's what enables a much smoother looking design.
However, for what you've described (landscapes and high ISO), I believe the 5D is unsurpassed dollar for dollar. I'd recommend trying a 30D first because it might do the job for less than half the price (and a third of the price of a 1D2N). And if that works out well for you, then there you have it.