More human diversity.
No, I don't mean Not-Fantasy or contemporary ethnicity/race proxies.
I want to see more Abhumans and Mutants. More minor, abeit unique variations that prop up from the huge genetic diversity and evolution of the species.
New vehicles. I really want to see cars, trucks and new Leman Russ variants. Ones that are closer to a steampunk or WWI level, others closer to a late 20th century design (which, on tabletop isn't hard to do for conversions).
Generally, I just want more diversity.