I saw this yesterday and it's amazing, which is an understatement. On top of your comments, it's also in 3D. The essence of the film is life in the trenches and surviving bombardments and that seems as real as you can get. The actual fighting scenes were more generic because it was hard for a cameraman to follow the soldiers into action. What makes this amazing is the 3D effect and the colorization. After the movie was over Peter Jackson talked about how he made the movie and that was more amazing still. For example, he had people lip read what some of the soldiers were saying and then when they figured out where that battalion was from, he’d have people from that area read the lines.
Another example was how they slowed the film down. WWI film was shot at different speeds than today. They managed to get every film down to the correct speed.
His attention to detail was outstanding. Amazing film.