Gods and Generals had some of the most stilted, pretentious, stultifying dialogue of any film I've ever seen. And I am an easy audience for Civil War movies, having liked Gettysburg despite some of the same flaws. Many war movies have the same weakness...excellent action sequences strung together with incredibly boring narrative or dialogue filler. Troy had some fantastic battle scenes bracketed with totally ridiculous soap-opera interpretations of the myths behind them.
Two other very good films :
Patton. Possibly the best view ever of the dichotomy of glory and horror that battle represents, and a great glimpse of the politics of armies. George C Scott was absolutely hypnotic in the role.
A Bridge Too Far. Courage and sacrifice of the ground soldier contrasted with the egotistical folly of their leaders. Again, great action sequences and Anthony Hopkins in a fine portrayal of the gritty Brit paratroop leader.