Some ideas:
-The Xyrk Empire, an expansionist alien empire composed of the ruling species, the titular Xyrk, and the nine conquered species, each of whom have had "Xyrk" put into their species' name as a mark of their servitude. The Xyrk believe that they're the inheritors of the galaxy, having risen from the ruins of an ancient interstellar civilization. Despite this, they are no fools, and seek to further improve upon these archaic designs. They use powerful weapons based on manipulating gravity.
-The Kasekh, a machine species possessing the minds of their ancient creators that had been entombed for a hundred millennia. They were first found on what first seemed to be an ordinary moon circling around a gas giant, but was revealed to be an ancient Kasekh complex which, as it was explored, began to awaken to their presence. In every encounter, they have proven hostile and incredibly dangerous, highly resistant to damage and able to quickly replace their bodies with new ones. Little is known about them, from their history to their language; just that one should be careful where they set their feet upon, for that world may be host to terrible secrets from ages past.
-The Golden Hive, a trade empire built by the Zyrin, a bee-like species noted for their delicious soporific honey, hexagonal organic structures, and well-developed diplomatic relations. Zyrin tend to be quite attractive, being generally well-endowed. They are split into separate castes, such as the muscular six foot tall warrior caste, the four foot tall worker caste, and the eight foot tall royal case. There are also the all-male drones, who are five feet tall.
