Finished the OVA recently, enjoyed it a lot, mainly because the characters on both sides of the main conflict are just genuinely likeable people. If the show was about a bunch of Grand Bishops and Rubinskys and Minister Langs vying for their own slice of the pie, forget it.
One thing that threw me a bit was the conflict between Oberstein and the other two fleet admirals. The seeds of that were planted near the beginning, when Oberstein went against Reinhard and allowed the Westerland nuclear attack to take place, and also when Kircheis died, because we later learn that Kircheis was forbidden from carrying a gun due to some change that Oberstein made. In my view, the Westerland thing (and Oberstein's other cold advice to Reinhard) is an issue of what a consequentalist viewpoint says is correct vs what a virtue ethics viewpoint says is correct. Oberstein is the consequentalist surrounded by people who primarily care about acting in virtuous, honourable ways, and the others resent him for not restricting himself to honourable military actions. It definitely makes sense for this conflict to occur, but I was confused by the fact that the conflict was set up, then simmered on the backburner for about 50 episodes until we started to hear Reuental and Mittermeyer complaining about the way Oberstein runs the military and does whatever he likes, or something like that. The viewers have already been shown that the characters' deep-seated differences in worldviews are in conflict, so why does the conflict get brought up by the viewers being told (not shown) about Oberstein managing bureaucratic stuff badly? Maybe it's the kind of thing that will make sense on a rewatch.