- The Bugs - Just what it says on the tin. They will eat you in the most painful way possible, often with lots of body horror. Typically can't be communicated with, often have a hive mind. Examples include the critters from Alien (and their descendants, the Tyranids and the Zerg), things from the Cthulhu mythos, the Vong from Star Wars, the Ithkul / Harvesters from Master of Orion, and the Shadows from B5. The bugs from Starship Troopers and Ender's Game fall here to some degree, but not perfectly - they're not using people as a growth medium. Infiltrators, along the lines of 40k's Genestealer cults or Duran from Starcraft, are not unheard of for the bugs, so their Intel probably shouldn't be terrible. Oh, and they breed like maggots. They often waste lots of bugpower just to run their enemies out of ammunition, though, so that might need to be modeled...
- The Scary Robots - Again, a straightforward name. The Borg, the Drakk from Unreal, the machines from the Matrix, the Cybrids from Starsiege, and the Necrons of 40k all clearly land here. Additionally, when we look at the psychological workings of these species, we tend to see relentless efficiency combined with a superiority complex. When we look at it this way, we can also add a number of humanoid societies here, such as the Peacekeepers of Farscape and the Imperium in Star Wars. Unlike the Bugs, in general people aren't useful to the 'bots in a biological sense - "Exterminate, annihilate, destroy" is the motto, or at best "Domesticate the inferior fleshy creatures", rather than "We will lay our eggs in your spleeeens". The Scary Robots can often be communicated with, but most of the time they don't care what you have to say (meatbag). Spying is something they often neglect, due both to their overconfidence and their issues communicating with lesser species. Some 'religious zealot' cultures may also fall here.
- The Noble Savages - Warrior cultures, typically with some sense of honor. Canonical examples include the Niven's Kzin (and their Aslan successors from Traveller), the TNG Klingons, the Luxans of Farscape, the Wookies from Star Wars, possibly the Skaarj of Unreal, and, to take things perhaps a little far, maybe even the Orks of 40k. The distinguishing rule here is "If you challenge one of these guys to single combat, will they play fair?" These aliens often lack respect for non-warrior cultures, which they see as soft and decadent, but can come to respect other powers who have proven themselves on the field of battle. They tend to disdain spies and diplomats, but often breed quickly and are excellent individual combatants, though sometimes poor tacticians.
- The Puppeteers - Taking their name from Niven's Pierson's Puppeteers, these aliens manipulate other species, time, and space in order to get what they want. They tend to be introspective, and may also be psychic. In addition to Niven, the Eldar of 40k provide a good example. Star Trek's Vulcans also fall here, as well as the Protoss, and the Delvians of Farscape. One interesting note is that most puppeteer species seem to have a dark side; the Eldar have the Dark Eldar, the Vulcans have the Romulans, and the Protoss have the Dark Templar. This suggests that the Jedi / Sith duality might also fit in here. Puppeteers are generally fully open to communication from other species... but they're likely to get the better end of the deal. These guys probably also have excellent spies / good intel - it models the "Farseer" aspect nicely. However, these species also tend to breed slowly, and may be susceptible to corrupting influences, as with the Eldar and the grasp of Slaanesh.
- The Unscrupulous Merchants - It's said that money makes the galaxy go 'round, and the Merchants are out to make sure it turns their way. Example species include the Hutts, the Bothans, the Ferengi, the Hynerians from Farscape, and the Bentusi of Homeworld. While these may seem initially similar to the Puppeteer species, the difference lies partially in the means by which they operate - no supernatural powers here, and while the Puppeteers are likely to have massive, century-long and galaxy-spanning plots backed by prophecies, the Merchants tend to think on much shorter scales and have more modest aims. They're also very open to negotiation, and are probably decent at Intel; sometimes corporate sabotage is the right tool for the job. Not particularly warlike or adept at the art of conquest, though very likely to cohabit space with other species. 'Pirate' species might fit here too, just by the cohabitation condition; I feel like Traveller's Vargr are likely here, though Homeworld's similarly-named Vaygr are probably Savages.
The second topic of interest is the Elite Officer rules in the Moderator's Companion. These feel like something which could be integrated with an RPG (say... Traveller) to great effect, which led me to the idea of running a combined VBAM and Traveller game in the same universe at the same game-time. Probably the best way to run this would be to have one set of players, each of which runs both an empire on a galactic scale and a single character in the crew of a small, Travelling ship. This creates some really interesting metagame issues, but frees the CM (moi) from having to come up with an over-arching plot, since galactic events will likely be decided by the agendas of the various player-run empires. Further, since a turn of VBAM is nominally a month of game-time, and the standard unit of time in Traveller is a week, this gives about four Traveller operations per VBAM operation, which would keep the game Traveller-centric, but allow things to unfold on a galactic scale. Having the second, longer-term game in place also frees up the Traveller characters to do long-term things that they normally wouldn't consider, like spending lots of time training, doing research, or in jail. On the flip side, given rules for translating Traveller and VBAM Elite Officer statistics, it would become possible for Traveller characters to influence events on a galactic scale as well. So it'd be a very, very interesting way to run a game, and quite possibly worth the little bit of extra paperwork that it would generate.