My Rules:

* No close inbreeding (sister/brother, parent/child, grandparent/grandchild).
* Monogamy whenever possible.
* No killing villagers on purpose, even the lazy ones.
* Retirement at around age 65 (I uncheck skills choice).
* Chief teaches once a day.
* As many villagers as possible will learn new skills & try to get to elder status.
* Begin doctors when they're still kids