Nice start, but as people said, detail is key. You look like you have a solid layout pretty much down, so now is a great time for you to start adding a little detail! Try looking at the arachnid2.map for some ideas, and think about adding boxes/crates, pipes, posters, fancy light fixtures, wall support, and random greeble to the walls.
Also it seems way to bright. Try lowering the intensity a lot, and work on lighting from multiple individual sources.