Fun stuff
Its always great to have the time, skill, patience to do up custom craft terrain completely from scratch. There's a wonderful sense of pride that comes with that.I obviously don't agree with the above designer's sentiments on not using 3D walls but OF COURSE I'm going to be a bit biased there
I think that if the system is stable and the walls can be removed or added on-the-fly as needed, that 3D walls add tremendous atmosphere and value to a terrain piece. Not just for looks but for tactical and line-of-sight issues, it can really help players wrap their brains around an environment and sometimes do creative things as a result.