Admittingly, I too have had difficulty understanding the big picture, having come out of Reformed Reconstructionism myself. So I totally get your world, and I had/have similar roadblocks. Where west operates on a very logial penal substitution model, broken down into a transactional imputation, I found that the distinction comes specifically in understanding how East understands primarily the atonement. Because I'm not qualified in any stretch to explain the distinctions, I would simply recommend this short video as a starting point:
https://youtu.be/55Z7S7wn77k?si=hGZjRdsetWbdO39w
Bless you