Generally, I like to see current themes (western, steamtech, victoriana, nightmares) expanded upon rather than adding new ones (highlanders, prussians, ...). Especially more steampunk stuff (I really wish the Smog minis were 32mm).
In no special order:
> A fanatic preacher
> Indians
> Dogs
> alternative Giant Mosquitos
> Civilians
> Tokens
> Houngan
> more Stempunk thingies (constructs, augmented characters), not necessarily more archanids
> steampunk vehicles (yes I play Deadlands too )
> a swamp kraken thingie climbing out of the swamp
> something with molemen