Negative Trait: Hates Driving. Mood penalties when driving, driving skill comes very slowly.
Mutation Branch: Sleeper. Get tired faster. Start sleepwalking. Move slowly while asleep, but gain bonuses in other areas.
Mutation Branch: Shade. Generally more sneaky - harder to hear you, or see you, or smell you, especially at night. Night vision. Squishy. Generate smoke? Be a spooky, sneaky, frail ghost.
Mechanic: Ambitions. Like Battle Brothers. Pick an ambition, complete it for a benefit. Find a new artifact, or kill a special enemy, or trigger a late-game event. Mostly I’m looking at this as an easily-controlled way of increasing stats.
Mechanic: Breakthroughs. Pick a reward. Get a set of objectives. Each time you complete an objective, roll a die. On a success, you get the reward. On a failure, increase the chance of succeeding next time you roll. Rewards may have skill requirements, such as high levels of first aid or fabrication. Rewards are mostly crafting recipes, including for things that don’t currently exist in the game world. Even in the apocalypse you can advance the frontiers of SCIENCE!