It took a while before I could get back to this project. We had a German exchange teacher staying with us for a little over a week.

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One of the most obvious changes is that I restructured the whole layout to waste less space on the map and allow for larger rooms. This let me go with 300dpi and still have a 20x20 map without the image size being redonkulous. The PCs also now have a choice of which direction to go first, which gives them a little more control over the flow of things.

Instead of going with a photo texture for this run I changed to a more neutral background and added a bump map overlay to give it a water-carved cave floor feel. I smudged and burned the bump map under the water areas so it would get gradually lower there. I darkened the water and added a dark to light gradient overlay to make the back end where the tunnel would be nice and dark and deep. (I'll probably still go even darker for the final version.)

I also took the advice of making the grid a little wider, although in the final version it won't be there anyway, since our virtual tabletop will add one at the players' option. It's just to give a sense of scale here.