But the loss of corruption and blighted lands is a huge loss.
Not hard to add in, just use GM determined encounters in perilous areas with Shadow generating encounters.
Note that the 5 categories of civilization (Free, Border, Wild, Shadow, Dark) have been reduced to 4, with 3 explicit: Border, Wild, Dark, and the implied Free (p. 113); Perilous is in a sidebar (p. 112) and would be applicable in a number of areas. rather than affecting the travel TN, it affects the nature of the encounter... Border is event type rolled with Favoured, dark with Ill-Favoured.
Note that the shadow gain is variable by civilization category...
Free: none
Border: fail=all 3/144, fail = target only 12/144
Wild: fail = all 12/144, fail = target only 24/144
Dark: fail = all = 21/244, fail = target only 36/144
Note that the journey events table does NOT include random combat encounters. I think this may be a bit of an issue. But it does provide for wounding.
Border: 1/144
Wild: 12/144
Dark: 23/144
Likewise, terrain is reduced from 8 distinct entries to 3: normal speed, half-speed, and impassible. A touch more effort required by the GM, but simpler and easier to use. And memorable.
A pure road bonus is easy... treat it as a beneficial circumstance and have the leader huck a die or two extra...