i agree crafty, actually. the point i made was that we want cheaper defensive. mobile units would seem to provide that. the feature of being able to move them, because they are mobile, has been advertised by the GM as a way to defend yourself with less hardware, because you can move them, ie they are mobile. lol
but yes, their is a level of build up with those, that is extreme. and not difficult. and true to sim country form, we will all build as many as we can. then no one will be able to do anything. which is not what we want.
i'd suggest a limit version. for instance, say 1 garrison, and say 3 ground units could respond, in addition to the normal target. those ground units could be mobile units, or regular defensive units, (not suggesting any changes to air d,) that way, it wouldn't be difficult to build a strong defense, but impossible to build an unbreakable one.
or even one garrison, and 2 ground units, from the player, and that can be matched by up to 1 mobile unit from fed mates. similar to air defense.
or even limited ranges, like 100KM for most the missile batts, and 35-50 for the light tanks and such. that'd allow the attacker the ability to gain access to the country, with out over whelming it. leading to "country resources," if you had to empty the ammo of all the units in a country, why not just take it? but if you can create your own military presence in the country, and attempt to move it toward the richer parts of the country... its interesting to see if that would be enough to make the war game viable, while lessening the effects of loosing.