Most mini games treat terrian as a hinderence to the whole play exerpience IMHO. With units that have to act as a whole it becomes a problem when just a few of them are in the woods and the rest are not, but you still have to stay within X of each other. Malifaux makes terrian everyones's friend, because you never worry about getting a unit stuck in some woods. If one guy gets stuck in the woods....you either had a plan or you did an opps, it's not because you ran out of room to place mini's.
Because of this, the less terrian on a table makes it easier for the gamer to process what he has to do. So I believe that we have been stuck in a rut of terrian = bad, slow play, clunky rules, and odd movement of units.
The first game of Malifaux in my LGS I placed a ton of terrian on the table. I thought wow that's way too much. We played the game, and it turned out to be the perfect amount. So, that's what I do now. the guild should only have a few firing lanes to really take advantage of. Which really makes up for their advantage of having guns.