Antinov is a ground operations specialist, and through he's undoubtedly the bird in charge of the entire battle-group known as the 24'th Autonomous Special Operations Fleet, his position and focus would make it difficult for him to directly oversee his command ship. So Antinov took a less experienced captain to command under him, as many an admiral do. Their might be a bit of nepotism in his choice, since Anavale and Antinov have been close since they were pups. But Anavale is a competent captain who's proved his worth time and time again, and someone Anti can always trust, professionally, and inter personally.
This black and gold uniform is the typical garb for commissioned officers and higher 'brass' in the Imperial military. In the fleets, the jacket comes with a shoulder cape and buttons across the chest with hidden buttons. For ground forces specifically, the high ranking officer's blacks have a more centred double-breast with visible buttons, no shoulder cape and epaulettes in either gold or crimson, depending on rank. One persistent complaint about dress uniforms in the Empire is how spread out the rank insignia is, as to discern a rank one most be able to see the shoulder boards, and cuffs from the side. Though straight on the chest bade and collar contain all needed information for someone who knows the insignia to determine rank.
On combat uniforms, such insignia is less relevant, as helmets containing augmented reality HUDs are common, and such HUDs give information such as rank when looking at an ally, even when visual markings are concealed thanks to information hidden in patterning on the uniforms, similar to modern day systems that display IFF markings only to light amplification goggles or thermoptics but are otherwise invisible.
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Art by Pig
Anavale and Verroth species are mine.