I don't really understand why Nog immediately defers to the cadets, given that he is an ensign
IIRC, Nog's commission was no more "real" than those cadets were. He was given a field promotion, just like they were. Indeed, it could be argued that the cadets - since they had completed some Academy training and Nog hadn't yet - were more entitled to command than he was.
Or, conversely, Nog could have just thought that he didn't dare pull rank on them because he was outnumbered. There were dozens of cadets, but only one of him. If he doesn't do what they say, they'll throw him in the brig regardless of how legit his rank was.
As for the episode in general: Agreed that Red Squad were arrogant and reckless and full of themselves, but I'm sure the Klingons would have loved it - the Valiant
crew died in battle against a superior enemy. That's the way all Klingons want to go. They probably sang songs about that crew.