You get the psychic hood as everyone, if you want to wear it with helmet or not is up to you. Most ppl for some unknown reason to me forget that Librarians actually wear helmets additional like here: As for Armor color, you may assume you run around in the blue color, as depicted above with just the gauntlets and perhaps the shoulder trims being in the chapter colors. Since so far everything is Codex-adherent, the Techmarine color will be the typical red with the Opus Mechanicum and all that nice stuff - Command Squad merely gets the fancy skull on the shoulder to make them look out. Sergeant helmets most likely just have a golden skull in the center which serves good enough as Sergeant symbol, as per Codex. Though among most chapters it is painted red and veteran helmets white.
Do you mind me being a darker blue lol. Im not a ultramarine but otherwise cool. Ive seen various standards so i like clearing that up.
I want it to be ocean's deep blue.....no no no wait....I want misty mountain blue....no wait i changed my mind....robin's egg blue...no wait i changed it again....
nah man the Iron brother hood thing I got out of a idea With the iron hands name and the way white scars have brother hoods, just a combing of names similar to blood Ravens.