Re: Saw blade for cross cut.
As for the riving knife, I am not sure if there is one default. Machines with bigger blade (thicker plate) capability likely come with thicker riving knives.
Riving knife, as you may know already, needs to be thicker than blade plate and thinner than blade kerf. I believe I had a 2.8 mm riving knife with 3.2 mm Kerf blade which had a 2.2 mm plate.
HTH,
Imran Malik
IAM Wood Creations