I've made my Jedi Consular "rakghoul" themed but was disappointed to find out there are no Rak infected customizations for Nadia and Iresso. It also turns out there are no customizations for several of the other original companions either. At first I thought the romanceable companions didn't have a rak custom, but Vette, Vector, Kaliyo and other romanceables have rak customs. Realizing that some comp maybe shouldn't have rak customs, here are the ones I think should:
Akaavi Spar
Bowdaar
Broonmark
Doc
Doctor Lokin (maybe? he already turns into a Rakghoul)
Ensign Temple
Jaesa Willsaam (Dark)
Jaesa Willsaam (Light)
Khem Val
Lieutenant Iresso
Lieutenant Pierce
Lord Scourge
Nadia Grell
Risha
Talos Drellik
Torian Cadera
Xalek
Plus, maybe some of the new companions?