I like the way these levels play. Because of all the nooks and crannies that are generated, it's a bit more unpredictable, so I feel more like I'm exploring, and it also gives a lot of opportunities to ambush. Of course, I haven't seen it with any actual enemies in it, and I'd love to see them added, to get an even better sense of the levels.
When I played, the sections you built the level out of became obvious fairly quickly, even before I looked at the code. I'm not sure if that's a bad or a good thing though.
Anyway, I'd love to see more level generators like this. It doesn't seem too hard to get the basics in, so maybe I'll try to make some myself.