Kol: Very experienced admiral. He knows what he is doing. Probably would have wrinkles, a and a short beard with a bit of grey in it. Perhaps give him a bit of an exhausted but attentively wise look to show his weariness of battle, but expertise at it. Basically, the iconic TEC guy.
Akkan: Some guy in a uniform that is very neatly pressed and looks to be middle-aged.
Dunov: May look a little nerdy and may be working with a computer or something...
Sova: Young commander that looks fresh and has likely never been in control of a capital before.
Marza: Semi-short, semi-fat guy exuding a very funky smell that likes watching things go boom a little too much.
Kodiak: Perhaps a younger version of the Kol guy, but less weary of battle and seeming to have more vitality.
Hoho: Mad Scientist. Since this is sci-fi, why stop there? Why not just go full out cyborg? You know, half his head is glowing and you can see little circuits and whatnot inside his skull. Perhaps have a prosthetic arm/leg or two... You get the idea. Oh, and his voicebox has to be prosthetic (given the way he talks)
Cobalt: A young, very fresh recruit standing at attention.
LRM: A slightly older more experienced officer with hands behind his back.
Well, there you go... My two cents...
Although ROFL @Rezo/Darvin