a post on the cdda subreddit brought up the idea of having quadriplegic as a bad trait(which if it could be added would add and an amazing challenge.) This got me thinking, what about having diabetic as a bad trait. your character would start with insulin and related pills needed.
The character would have to take before eating or maybe take once when you wake and once when you go to bed. Could also add the chance of sugar spiking or dropping(like the asthma attacks)
Human waste and bowel movements
hear me out lol.
striving for realism , at some point in the cataclysm your hero is gonna have to take a moment to relive themselves. toilets would be best option but you would need to make sure the house was clear. or if you prefer all natural you can dig a pit do your business and fill it up. Also say you eat something rotten… it can make you vomit or poop yourself. With crap in your undies you either find a quick change or go commando, or don’t change and risk the zombies and other things smelling you.
it can be filtered in a worst case scenario to drink. it would be disgusting but it would keep you from dehydrating. Could also use it to lure enemies away.
Sewing kit, needles, and thread should be used as a way to stitch wounds.
character with very high medical and fabrication skills would be able to craft body modifications. for ex: character steps on a land mine and blows his leg off. once you get the bleeding to stop and you get the materials you should be able to fashion yourself a fake leg(out of heavy stick metal, etc.
another example on the extreme end of the spectrum. your character could construct spikes and secure them to the bones in the hands(wolverine) it would be extremely painful and risky. And it would require lots of skills and etc.
it would be cool if you could tame the dogs, and other regular wildlife. use chains to secure them to your place of residence or have them in the vehicle with you. or if the situation arises kill and butcher them for meat.(Animal breeding would be awesome and provide with decent food supply)
There should be a net type trap that zombies and players can get caught in. if a zombie get caught it would be cool to chain them up and have them tow along with you(walking dead obviously)
It would be cool for characters with right skills to dual wield weapons. Two swords,pistols, etc.
for the CBM fanatics it would be great to create powered limbs? arm damaged to the brink of death. get to a lab and get the gear to make yourself a robotic arm or the like.