Alliance are a serie of different mods. On the Star Wars GC, you can play the civil war Empire vs Rebel era + Black Sun and soon the Republic and CIS.
Editing the new Nebula SD made by Evillejedi, I have made the Endurance from the Star Wars The Essential Guide to Warfare. For me it will be the KDY Endurance, a heavy carrier with a design and a size similar to the Nebula SD or the Defender SD.
You can see more screenshots here. Firefoxccmods.com