I am sure this has been brought up before, but I think there should be some sort of movement restriction with spaces adjacent to armies. Nothing in the world is more frustrating as my army sits there picking its butt as some random woodland creature walks around them and then destroys the city behind them.
There are a couple options I think to make this less of a problem: A) Make adjacent spaces to armies blocked for movement (ala civ 2),
Make adjacent armies fight as one (ala the old HoMM style), C) make moving into an adjacent square attack the army if hostile conditions are relevant, D) give the army that is attempting to be bypassed a choice to intercept