Howdy, Neil. Always good to see you posting.
I agree. I often get "stable sweepings" from local horse farms, a mix of manure and sawdust. Most folks clean their stalls and throw it all in a pile, huge piles eventually, and it all breaks down. The best stuff is at least a year old, very crumbly and ingredients are "unidentifiable"...exactly what you are looking for in a such a product!
I do lime the soil from time to time but usually only every 3 to 5 years and mainly to bring the pH up to neutral. I don't think I want to lime it every year then add something else to bring the pH down. I'm the lazy sort, ya know! :>)
Gypsum would be a good ingredient to use to help with "crumbing" up the soil, don't you think? And it would not alter the pH while doing so. Or do you have access to gypsum over there?
Shoe (who enjoys your photos very much!)