I'd buy the taking the backseat, if not for the 50000 year war raging on their doorstep over whether they would get exterminated by an alien race from another universe. Surely they did something? XD
Also, what was the benefit of the economy being opened to other nations if most of those nations were obliterated or taken over after going through turmoil? The only potential partners (By that I mean the ones which survived the Universal War and were known by the Sazkarjhit prior to the end of the old thread) would be Hachers faction, who went through massive political change and likely socio and economic as a result due to a takeover, and my own who don't even have a concept of money.
It seems this is the same faction, so what happened with the Reapers? How did they avoid being seen (I assume that's what you mean by their fleet sizes swelling, which would be pretty hard if you are having to fight a massive empire from another universe)
"Collective: Darkwolf. Research guys, survived Reaper war/technically won it but lost a bunch of people in the process." Add to this authoritarian, big brother, brutal, producers of war machines from living beings, eugenics and group-before-individual mindset and then you've got the right idea. Cause you know, grimdark
Dwarves: basically what hacher said
Equestrians: Basically what Hacher said. They are basically MLP in space, makes about as much sense as you might expect xD
Humans: Technically not humans and more along the lines of terrans. They're sort of the inbetweeners. While the Equestrians are basically utopia because it lacks problems and the Collective is dystopia to solve its problems, the Terrans are neither extreme and are essentially a socialist Western country
Sazkarjhit: Think Elites from Halo and you'd be on the right lines. Tough, skilled and honourable warriors with a dedication to their gods. They're important because of their soldiers skill and tenacity. They arent the most advanced or the largest, but their soldiers are top dogs for individual skill.
Castullt: What Hacher said. The original Hach were pretty decent though, there was more focus on their culture than massive fleets, it seems
Supremes: They're the last of a dying race. They generally help the people of the galaxy when its needed, but they can turn nasty if they need too and individually they are extremely powerful, so its not a good idea to try and turn them against you
From the others I have yet to see a post, so I wont say anything xD