BCFiles serves up Cakuzma's Target Separation v4.0 script, which allows Galaxy-class starships to separate. There are additional mods which must be installed; requirements are listed on the linked page.
Hispania Revolutions Mod Beta v1.101 can be downloaded from Lancers Reactor or from Kryosphere Studios. Another mod by KS is the Music Mod v1 (also at Lancers Reactor and the KS site), which allows the user to select music styles for each House.
The Babylon Project is soliciting voice actors for a sixteen-mission run. Full details and instructions can be found in this HLP thread.
REAxion offers a new version of HardLook, which is compatible with UIM.04. This thread at Captain Zedo's has a download link and more information about the program.