You have the small stuff covered, nice to have the 7-13mm in there too in a small quantity.Lol, I did think of you when I was putting it together.
By small do you mean small ratio or small in size?
I was planning on using liquid kelp weekly, just didn't mention it in the mix info.
By Neem do you mean a neem oil soak?
We don't have any wandering cats in our yard except ours who are only outside when we are, and our small terrier dog won't be able to get up and in it.
Are we talking double, triple the biochar and wormcasings?
No problem adding Scoria, maybe 2L?, you said to beat it smaller, do you have to crush it? The size it comes does seem too big though.
I like Neem cake as I feel it helps with IPM a bit. Lots don't like it.
Neem oil as a foliar in veg maybe to knock off anything you don't like.
Use a good mulch, Lucerne is excellent.