I was looking at medievalthomas' excellent D3H2 amendments and he has included an excellent table for DBA 3 terrain but it reminded me of an irritating issue with Rough Terrain. Why are their four types of rough terrain but they all have the same effect on the game? Why can you only find boggy ground where there are farms? Why are there no rocks, scrub or bogs in tropical lands but an abundance of paddys? Wouldn't the occasional tropical rain cause some mud? I wonder if anybody has spent time discussing whether the "or" between rocky and scrubby for dry terrain is absolute or relative.
I am ranting because every now and then people will mention how brevity was key during the rule development and yet this precious space was used here rather than on the more complex mechanics that we keep discussing 6 years after publication!
I suppose we could always assume that armies in Tropical regions don’t fight during the monsoon season, but wait until the weather improves. Or all those Marshes DO already represent muddy rain soaked ground...
I do like the idea of impassable terrain. Your mountains could be elongated and placed along the flank to allow others apart from Littoral, narrow the field. A Hilly, Ps/Aux heavy army, could narrow the field, place some woods and hills and wait in ground of their choosing.
But at least your impassable terrain have relevant differences that make them unique and worth considering. The weather rules I adapted from DBM/DBMM allows for boggy ground to freeze or get worse with rain. Maybe the invader must attack or at least move towards the enemy until contact. DBN does that. To compensate the invader may be allowed to refuse the first battlefield? The home army can then either take the role of aggressor or reroll terrain. It only takes 5 minutes to set up the battlefield.