I don't think there is an incest issue. Barry and Iris have been best friends since they were kids, even before Barry's mother was killed, and he's been in love with her just as long. The fact that they were raised together may imply a sibling relationship, which isn't entirely incorrect, but everyone knows that they…

Did anyone else catch the Batman name drop, thus confirming his place within this universe (unknown if it is "The Batfleck")?