I've been thinking about Kirsty. The present relationship with the Sausage King has been set up to happen from long ago.
The Brenda thing was just an interlude - clearly they had opposite ideas about the future (although she was a whizz with the marketing allegedly).
Kirsty is a perfect candidate for the compliant, child (and sausage) producing farmer's wife. She will fit nicely into the Ambridge mould still warm from the production of Jill, Peggy, Rooth, Shula etc - no amibition to travel further than Darrington and no aspirations to own any footwear other than wellies.