I think all us raptor SD owners know the culprit is the tiny discharge opening. Just not good for getting out large volumes of material. That said, Google "Honda mulching" blades and you'll see their "quadracut" set up. Kind of interesting to see the different blades stacked. The top one looks pretty light wt. I think people who own these Honda like them.
Gotta give you credit for being a pioneer....you have bigger kahunas than me! Good luck...be careful..let us know how it works.