I really enjoy Franklin and Valeria's place in the MU. I know they are problematic elements when it comes to dating things and time passing, but as a parent of increasingly precocious kids, they add an element that is really special and unique, one that I don't think could be fabricated or easily replaced. Some of it is hope. Some of it is wonder. Some of it is the blunt response you do get from kids. Your comics are a richer place for them.