I think blender would be a good option for more complex things. Here's a quick example I whipped up.
This one is just a render with some Ambient occlusion added. Under the render settings, The scale is down to 17 percent and Anti Aliasing is turned off.
![Image](https://dl.dropbox.com/u/38920518/Castle/Castle render AA.png)
![Image](https://dl.dropbox.com/u/38920518/Castle/Res.png)
Make sure your camera is set to orthographic for a more isometric look. The angle of the camera is about 45 degrees. (It was actually the default position)
![Image](https://dl.dropbox.com/u/38920518/Castle/Orthographic.png)
This one uses the freestyle build from Graphicall.org
I used the uniformpruning_zsort Python module.
![Image](https://dl.dropbox.com/u/38920518/Castle/Castle render AA with freestyle.png)
This render uses the same technique shown
hereAdjusting the diffuse ramps to give more of a 8/16 bit look is the trick here.
![Image](https://dl.dropbox.com/u/38920518/Castle/Castle render with freestyle.png)
So just giving another example. Nothing wrong with doing it by hand either. This way (if you know how to use blender already) is a very fast way of getting this kind of result. This only took me about an hour. Of course, adding more detail will take longer
![Smile :)](http://game-editor.com/forum/images/smilies/icon_smile.gif)
Here is the
Blend file