Have you thought about limb dismemberment yet? For the cannibals sake?
Boarding up houses, crawling through windows, climbing fences maybe ? Craftable and usable furniture? or emotes to use them? or more emotes and interactive things? grave markers? cemetarys, more things for the biological teams to use ? Clothing items that do their job? gas mask, med mask. Clipping.
P.s. Romero Zombies settings and animations, A LOT MORE ANIMATIONS! OPEN THE POP CANS WHEN THEY ARE BEING USED! IMMERSION. Please get in touch if you’d like any more award winning ideas for free, I love dayz. I wish it the best.