I understand. My first application was refused as well because I was complacent and provided the bare minimum of what was asked. Upon receiving the refusal, I researched in detail, spoke to many people, both professionals, and past students to really make sure that they weren't able to refuse my second attempt. Obviously, most of us are genuine students but you have to think from the perspective of an officer who has no idea of who you are and what your aim is. In the SOP, you have to clearly outline your background, your intentions with specific and detailed information backed up by documentation. It has to be detailed enough to show you know what you are doing but also easy enough for someone not in your field to understand what you aim to do.
You are in a state where, as I mentioned, your history of past applications will drag you down, no matter what you do. That's why it's so important to spend a lot of time on your application. If you want to spend the money and the time for a legal challenge, you can. There's no guarantee. On the other hand, you can use this experience to formulate a stronger application in another country.