
What I like about Barrow Oicunn is he represents the average Imperial officer.
He was an officer in the Humbarine defense forces during the Clone Wars, lost his family, and had his faith shaken in the Republic. Especially since Humbarine got its forces siphoned during the war, which left it vulnerable to a devastating attack by General Grievous.
Despite Oicunn's disenchantment with the Republic, he continued serving it, though he believed the Republic in its current form couldn't win the war. As such, he welcomed Palpatine's new Empire with open arms, though the Jedi Rebellion did cause him some concern.
During the Clone Wars, Oicunn invented new tactics while working within the confines of Republic protocol, tactics that were seen as inspired. It was probably because of this that earned him a posting aboard one of the Venators stationed at the incomplete Death Star, and the rank of Admiral later on.
In short, Barrow Oicunn's backstory is a good example of what the average Imperial officer is like, Alhamdulillah.