It would take a little bit of work to add graphics, but it wouldn't be the end of the world or anything -- I think people might want the mouse first though. Either way, we'll figure out what kind of priorities these are once everybody has played a bit. I don't want to rush into it or commit to anything at this point.
Anyway, there are lots of people that would say this isn't pure ASCII since I'm using the IBM extended characters. I did put in a little hack to support the 128 character people, but... well, there's a limit on the information you can convey with lower ASCII! It's almost impossible to play (although I haven't tried to select the 128 characters carefully). TT suggested as a joke having a chair in 128 mode be displayed as C-H-A-I-R cycling through the letters one by one. I'm not sure what else the purists could want... there are too many important distinctions to make with the furniture, especially if I want to reserve letters for creatures. If you don't reserve letters for creatures, people that are used to these text games would get heart attacks whenever they build an emerald door.
Right now, the cliffs are still straight, although that wasn't supposed to be north-south, since the perspective is relative. What I'm working on now is making swamp sites look like swamp sites, and making glacial sites look like glacial sites, deserts like deserts etc. At first, everything was just a temperate forest. Most of the changes are done, but there are a few outstanding issues mainly with trees and wildlife.
Later on, I'd like to allow different cliff shapes, for a variety of reasons -- right now, it would be a bit of a hassle, since the dwarves can think about things like "inside" and "outside" really easily the way it is now (they just look at the x coordinate). On the other hand, I've also got these other map bits that let them tell inside from outside in a different way, so it's easy to change... but there are lots of things to work on...