As you mentioned, pathfinding is a computationally intimidating problem (I've
messed with it for ships, and as sailors can tell you, it's not perfect

).
A few things make it more of a pain on here: you probably want to path find
over a long distance, which naturally extends the number of paths
geometrically. Terrain ep costs vary seasonally now, which isn't really a
biggie since seasons don't change often. Players have hiking, racial
abilities, spells that affect ep costs. In short, pathfinding on batmud is
royal pain of a problem, and I would be very surprised to see something
implemented.
Now, following roads is an interesting idea, and seems within the realm of
reasonability cpu-wise to me. However, as far as I am concerned, there are a
large number of projects that I want to work on before tackling that. Dunno,
maybe some arch will approve the idea, and maybe some wiz will volunteer to
code it. As I just mentioned, I fall into neither category, so can't say what
will happen
I'm aware of the "sometimes it's nicer to walk on plains than on trails"
problem. I have a couple of solutions in mind, and we'll see how that turns
out.
We're getting there, but we're not quite done working yet
Melemkor