[s]If you're still accepting people, I had an idea:

The Procyon Sector Authority. Basically a few systems around Procyon as the central system formed together and (very recently) declared independence, which is quite exciting since Procyon is pretty close to Sol (11.4 LY). Systems, I thought about to join it are, for example, Luyten's Star, Sirius, Ross 614 and a few more around that area, especially mining systems. 
Since they are so close to Sol, they are pretty much very old colonies, with quite the population and a strong, mining based economy as well as the Procyon Shipyards.
Of course they will never have either the military or the economy to challenge a huge empire, but they can be self-sufficient and also defend their borders.

How does that sound?[/s]