What settings should i adjust in SP so that shotgun weddings dont happen by default but are more influenced by the couple's traits and circumstances? I know about setting the option in Sp under the pregnancy tab to false, but it seems like none of my couples with kids out of wedlock ever contemplate marriage, be it shotgun or planned.

anerdnamednova - I'm not sure there is a way to influence the Shotgun Wedding scenario other than the way it's already done. If SP > General Options > Options: Pregnancy > Always Married Unexpected Parents is set to False, whether the parents are pushed to get married is supposed to be dependent on their traits and whether they would be conducive (score positive) for marriage. Might there be other factors in play, such as these sims are typically already partnered to someone else most of the time or have marriage-unfriendly traits such as Commitment Issues?

Yes, Arranged Marriages (SP Relationship module required) will force sims to consider marrying who might otherwise not do so, if they are compatible with each other, but that sounds like a lot of work on the player's part to do this on an individual sim basis. What sort of Arrange Marriage: Caste would make this easier on the player? As I read the documentation, using a caste for this will set up one Arranged Marriage for the target sim with some sim who qualifies (is in the designated caste), but they may not be the other parent of the unexpected pregnancy.