So this is an updated version of my Mueller's Marauders insignia. Right now it's just a Fed Suns logo, so I'm going to add a Marauder I to the image to make it specific. Anyway there is symbolism here.
The pool of blood in place of the standard red is to signify that this unit is born out the blood of the Fed Suns civil war and the conflicts of that era, just as the sun rising from the pool of blood signifies that the Federated Suns is rising again from the same era of violence. The sword is a Spatha, which does not accurately represent the Roman Republic which the RotS is based off of because the Spatha was used towards the decline of the Roman Empire and afterwards, but perhaps it signifies that this unit will be instrumental in the downfall of said Republic? Other than that the colors and shapes are just flashier representations of the old Fed Suns logo.