The last model has hangars on the side and the glow color from engines is green. The unit on mod is a little different because it transports fighters but it is more powerfull than other spaceships. It can use one heavy green blast and one power to weapons abilities.
If you want know about Relentless, you can go here.
About Rebel Alliance, it has the MC112, other heavy carrier with powerfull weapons. I will put some shots.
About the mod and the release date. It is near.