I'm planning a trip with my girlfriend in a couple of months to either China or Japan. We currently have refundable tickets to Beijing, but switching to Tokyo or Osaka would not be an issue. I'm not sure where we should go.

Here's the basics:

-I've been to Beijing before and loved it. She's been to Tokyo before and loved it.
-Cost is not really a huge consideration. If we go to China, we'll stay in nicer places, but that's a tradeoff we can deal with.
-We'll have a week on the ground in either place.

In China, we'd be looking to:

-See the major tourist sites of Beijing, plus the Great Wall
-Visit the terra cotta soldiers in Xian
-Experience beautiful countryside (where would be recommended for near Beijing?)

In Japan, we'd be looking to:

-Enjoy the peace and quiet of Kyoto, and stay in a ryokan
-Experience the hustle and bustle of Tokyo (mainly in Ginza and Ikebukuro)
-Visit the parks and temples in Tokyo and Asakusa

On a personal note:

-I'm really into the historical aspects of places I visit.
-She's interested in natural beauty.

I know the whole "China vs. Japan" thing is a difficult issue to decide. And frankly, I think they're both worth visiting - on separate trips!

So, considering that we only have a week to accomplish our "goals" on the trip, which would be your pick, and why?