I'd suggest looking at the existing map layouts, trying to figure out what works, what doesn't, and why. Then try and come up with a layout that would be good for those same reasons. It doesn't have to be terribly detailed, really. Just an indicator that you can walk from point A to point B, and where res towers go. Bear in mind the basic layout guidelines. It should take > 30 seconds to run from MS to a hive. (I think it's supposed to be even longer, but most maps nowadays it's about 30 seconds) and no hive should be much closer or much further from MS than any other. Resources should be distributed evenly, one in each hive, one in MS, and then a few, but not too many more, inbetween them. I'm a big fan of choke points, but not so much one of double nodes. I'd rather have a map without a double node, or if we really want one, a double node that's almost impossible to defend. Those can be fun.
But yeah, a layout should just be a layout, don't worry about details or anything pretty. Don't really worry about where ladders go, or even vents, or elevators and such. Just a 2-d layout so we have something to start with would be great. If anyone wants to make one, it'd be a great starting point. I would, but I don't have any webspace to store anything on...