I think “prone to headaches/migraines” would be a killer negative trait to implement.
Could you imagine trying to survive whilst suffering a massive pounder of a headache? Give it something like -1 STR, -1 DEX, -2 INT, -2 PER for a headache, and -2 STR, -2 DEX, -4 INT, -4 PER for a migraine, and we’d have a really challenging negative trait to deal with. Throw in more distraction from mounting pain…
Yeah. Keep that aspirin handy.