I had the same impression Grismath... I think it's the low resolution and lack of bilinear filtering combined with the use of those stone textures...
As for the comment referencing DF's textures and architecture as being boxy and bland just isn't true. To some extent boxy is, but this can be overcome in ways... and if the level is well made, it's not very noticeable. A current example would be what's been seen of DT4, and one of my other favorites was always Code Red... In regards to texturing... well, I've always found DF's textures to be just beautiful when used right.
Sorry, just had to defend DF.
Other than maybe those stone textures... well, actually green one should change too... yeah, pretty much retexture all of it. And please, stitch your textures. Those stone ones would look nice I think, if you chose a more appropriate ceiling and darkened everything a bit. If you really can't do the lighting (which can be confusing due to the odd way it's handled...), you could always try using sector lighting... It'd actually be more like DF then, lol. But, it's an easy solution for new editors, until they get used to vertex lighting. It can be useful at times, and can get better results depending on the architecture for those used to vertex though (without doing a bunch of cleaving and rearrangement and tweaking, I mean). Anyways, to do this, just set the one light to a near 0 intensity, press control+l to run lighting. Then go through in sector mode, and set what you think is an appropriate lighting value (0-1... 1 being fully lit, .5 half lit, etc). It doesn't get some of the nice effects you can get with vertex lighting, but it's better than nothing.
(Ok, admittedly, I was bored as hell when writing this post...)
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Wolf Moon
Cast Your Spell On Me
Beware
The Woods At Night
The Wolf Has Come
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Wolf Moon
Cast Your Spell On Me
Beware
The Woods At Night
The Wolf Has Come