Michelle,
You seem to have the basics covered pretty well. You have grass, comfrey, woody trimmings all chipped up. That’s pretty good.
Off hand I can think of two things that can really get soil getting healthy.
Option one is to get an aggressive fungus like oyster
mushrooms or wine caps going. You will need to get the spawn first, but wow do they make a difference.
Option two is not for everyone. Have you considered using your own
urine as a fertilizer/compost activator? It is high in nutrients and if aerated properly, does not smell. I always apply mine diluted, mostly to make it spread further.
These are just two thoughts—you are already off to a great start.
Eric