Sorry if I'm posting too many questions!

I want to be able to simulate the player making a single weapon swing. I want it to be completely scripted, but work just as though the player had actually hit the attack button (plays appropriate attack animation and does appropriate damage including poisons to the target in front of the player).

It's possible to do this with debug.sendanimationevent, but don't. Using that in one of my scripts has caused massive issues for some people.

You can use http://www.creationkit.com/SetPlayerAIDriven_-_Game, and then apply a http://www.creationkit.com/UseWeapon_(Procedure) package.