So it "actually" make things worse? It is funny how you conclude things... 16 squaremiles is not small by any means, especially when you have grand mountains that puts the y-axis to more use.
Moreover, Oblivion felt really empty(a big nothing) in a way so they could easy triple the content and it still would feel realistic. And I don't know about you but I would rather not spend one and a half hour of running until I reached my goal... I do have a life outside of Skyrim. I would say that what I have seen indicates on a really really good world design.
You do know that mountains take a lot space, right?
16 squaremiles is incredibly small for 150 dungeons, over 100 points of interest, 20 towns and 9 cities. Point out all those things yourself on a scaled map and see how much room there's left
![Wink ;)](http://gamesas.com/images/smilies/icon_e_wink.gif)
I'm not saying that it should incredibly big, just bigger or even just a bit bigger, so don't try and turn my argument against by using argumentative faults.
It's definitely not good world design to have it so you find a cave every 30 seconds and where you can cross a (at first) huge looking valley in 30 seconds. The best world design is to have it so it feels natural, yet not so big that it becomes a pain to travel everywhere.