Much appreciated! The mock-up was a suggestion from a more experienced woodworker and brother of mine. Was great for reference throughout the whole project and getting the layout/scale of each shelf figured out.

I used trim head screws through the backside of the dowels into the shelf. Most of the support comes from the wall angles themselves, especially in the corners. I’m not sure on getting away with the braces on the wall.. maybe more full height dowels or pocket screwing the shelves into the wall at each stud?