I'm a bit confused by the calls for another zoom level. Doesn't a higher resolution just mean you can see more because you have a larger screensize without compromising the size of things? I mean isn't the text on 800x600 on a small screen the same size as a 1680x1050 on a big widescreen? So I don't really see why you can't read things.
The closest zoom level is good to play in places like Iberia, France or Italy, while in regions as Rusia or China is better to play at mid level zoom.
But in the german region of Europe there are too many provinces/countries/banners/armies and even at the closest zoom it's hard to point the desired item. The wide screen resolutions only adds more provinces/countries/banners/armies to the left and rigth, but not address the problem. That's why people ask for another zoom level.
Also, in 800x600 the left panel (the one where you read ecomonic sheet or move slides and internal policies) is 300 pixels high (half screen) while in higher resolutions this same panel is also 300 pixel high, so the higher resolution the smaller is such panel... but this is not an issue related to zoom.