Starting from scratch on rocky, bouldery ground. Your thoughts on what I'm doing

The main thing that stands out to me is your manure and wood chip proportions. Horse manure on its own has a good carbon to nitrogen ratio for composting. Using 1:1 manure and wood chips might reaaaally slow down the composting

James Hird wrote:

Building soil is my main priority. There is no garden without it. I think I need to add more deciduous mulch to my piles.

Here is an excerpt of a movie in which Helen Atthowe talks about soil, maybe you'll find it helpful: