The Alliance mod comes now to Sins of a Solar Empire games with all the space units which you can find in mod from the Star Wars Empire at War Force of Corruption.
Another hero, Booster Terrik and the Errant Venture. Now if my mind is correct, I will add only three more rebel heroes, Mirax Terrik, Kir Kanos and the General Garm Bel Iblis. I should add them the next days.
About other Rebel additions, I will add the Bothan Frigate and Blue Diver from Warb_Null. I do not think that I will add more starships for rebels.