You could mix in a few regular empire minis that are a bit cleaner and have the zombies as blood swains (a little blood at the neck and slightly paler than usual), some of which have passed on and been raised again to continue their service rather than just the general corpse plundering of less evolved bloodlines. Mix in a few zombie parts and then you can have a progression from the live ones in the front rank to the fully decomposed guys struggling to keep up in the back rank.