You'll be surprised as to what Goldsource is still capable of.
Hunteh: In that first shot, the floor part looks good, but the ceiling looks horrible. I'd suggest a texture change, as well as the addition of detail brushwork to spice it up.
As for the second shot, the textures are very strangely aligned. Using Alt-Right click while using Lift and Select is a really easy way to get 'em aligned to each other. This shot lacks detail: instead of having it all textured with the metal texture, break it up. Add horizontal trims (ones that still follow the shape of the chamber) with a completely different texture.
Never assume that Goldsource can't handle it, because most of the time, it can.