I have another idea for characters. Genetic Diseases. Like in real life, it's possible to inherit some sort of disease. Each character will have a disease 'varible' so to speak - [ carrier, inactive, active ]. A carrier means that the character has that disease, but it won't affect them. Inactive means the character has it, but doesn't feel the effects. An event could trigger the disease (i.e., the character reaches a certain age). To keep things simple, I'll have just one type of disease. This could simulate the 'inbreeding' done by royalty lines (as the royal family usually marries within their family). If only one parent has it, there's a 50/50 chance. If both have it, there's a 100% chance that the child is a carrier (and a 50/50 for inactive).
If the characters are related to each other (say, cousins in a royal line who are a prince and princess), there's a higher chance of disease forming in the next generation, thus starting another line.
Come to think of it, there could be maybe 3 classes of genetic diseases:
common / crippling / fatal.
common has no effect on life span, and would be an annoyance. I don't mean something like the common cold. Things like a minor deformaty, disease in old age, etc.
crippling may have an effect on life span. These range from say, blindness to organ conditions, to crippling deformaties.
fatal would effect the life span, such as diseases of various organs (lungs, heart, liver, brain). The discovery of medicine has a chance of inserting fatal diseases, which is lessened by the Cure for Cancer and Longevity wonders.
This would go along side with the normal diseases. communicable and non-communicable. Diseases would have to be major, like Malaria. Current techs could even bring the onset of more diseases, like trade.
(I feel like I'm reinventing the left out feature in Civ3)