The seemimgly immortal, revered officer, the hard-nosed NCO who saves everyone's ass, the wide-eyed volunteer who loses his soul, and the wannabe writer who documents it all. Most bothersome to me were some of the demonstrable lies in the narrative put in purely for drama.
That said, it compares better than other portrayals of Pacific theater. I recall seeing some old John Wayne movies where the "Japanese" are actually Hispanics. It's almost comical to watch. Parts of Flags of Our Fathers were decent, but I found the structure of the flashback/present day mixture to be distracting. IMHO, The Thin Red Line was the dullest, most ponderous movie about combat I've ever seen. Nolte had the only redeeming performance in that POS.
For example, there was NOTHING in Leckie's book regarding the loss of religious faith he experienced in the series.
Pure editorializing by the screenplay writers.
In decades of movie going "The Thin Red Line" was the first one ever to put me to sleep.