Would be good to add the famous IG regiments such as the Armageddon Steel Legion, Death Korps of Krieg, normal Cadia regiments, maybe you can give them the Krieg Death Rider as a heavy cavalry/Lancer unit for their cavalry?
A few famous regiments ^^
Also this can also be IG cavalry, the image is a Rough Rider (Its not a Hun)
Catachans can be light infantry ^^
Just my suggestions