Have you actually used a 14" laptop with a 1600x900 screen? When I got the X1 Carbon, I was worried that I was giving up a higher resolution screen in order to get a ThinkPad ultrabook. But I've found that even 1600x900 is actually too high a resolution for me, without scaling. For example, I've got HN scaled right now to 125%. A friend of mine has an ASUS ultrabook (the Zenbook Prime UX31A) with a 1080p screen and it was impossible to read anything on it, the text was so tiny.

You can read about my experiences with the X1 Carbon here: https://news.ycombinator.com/item?id=4848375

I'm typing on that same laptop right now and loving it.