If it isn't already doing so, your lighting algorithm should react to solid tiles. It would look great.
You mean like this?[url]http://zippy.gfycat.com/ScaryNegativeAoudad.gif
I know it's hard to see in the gif but only a little amount of light bleeds through solid walls. It took about 2 minutes to implement and is tweak-able meaning I can adjust how much light bleeds
You can see it a bit better here:
Notice how the colors remain in their own section and no light bleeds into the bottom two sections