back to that map and tried to create more of a 3D effect. After a couple tries I didn't like how things were progressing and ended up scrapping an hour or two or work. I got to watch/listen to some "classic" movies, and I learned what doesn't work, so the time wasn't a total loss.
After those initial missteps I just ended up going back to my work-in-progress files to where I had every level on it's own layer and simply created the same drop-shadow to each layer. The effect was pretty good, in my opinion, right up until the point where I did the stippling. With the stippling the effect is a bit subdued except where the layers overlap.
After re-doing the stippling I went ahead and added a floor texture. Nothing fancy.....
Like usual, clicking on the lead-in graphic gets you the hi-res download (or use this link). You can view/download the low-res on the right.