The DF code, as some have gathered from old (and perhaps leaked) portions and Toady's own admission over the years, is not elegant but is a stunning amalgamation of complexity. It is the work of a mathematician.
How many lines of code is Dwarf fortress (roughly)? What is the most complex part of the code base? Which parts do you most like and which parts do you dread?
Doing a search for semi-colons, I get 260,000 lines containing at least one semi-colon. That overcounts on the comments and undercounts on a lot of the conditionals or lines with multiple statements, but it's the way I know to get a good rough count quickly.
The new equipment management stuff has gotten fairly intricate, which is probably why it has problems. Loading/saving/generating map sections and moving them around has to do quite a bit of bookkeeping. I don't think any of my code is elegant, if I could even tell, and I don't really have favorite parts, but I appreciate my past self when I come to extend a section and it is already prepared for me. Generally, I dislike the oldest sections, especially the pre-OO** stuff which still makes up a good deal of the code and is rooted out over time as I add things.
http://www.reddit.com/r/IAmA/comments/cuvnl/tarn_adams_creator_of_dwarf_fortress_his_response/Baughn was not chosen, it was more so that he is someone that has shown himself to be trustworthy, having helped Toady on numerous occasions with a bunch of various matters, met Toady in real life, and he has an intimate knowledge of programming in areas that Toady is not a specialist in - which led to the SDL DF version, openGL, and framerate optimisations. It's also worth noting that even Baughn hasn't seen most of the code, just the parts pertinent to the graphical updating and unlike some others in the programming know - has never done anything stupid with his knowledge.
Perhaps some of you were not around at the time, but there do exist people that try to backend DF for the sole point of leeching off game code. One jackass almost got Peterix of DFhack fame banned in the last round of stupidity.