I've known people who would look at a piece of art and say, "Meh, I could do that." And I think they miss the point: the artist did and the bush-league critic didn't. The reason that the artist did and the bush-leaguer didn't is because the artist cared about making it happen enough to invest the effort required to make it happen.

Over time, I've come to give some credence to the idea that not implementing some spark of imagination is a good indicator that I don't really care that much about the idea and that the ideas that I implement are probably things I really care about.

Just from the high level description, it seems to me that you care about going to law school enough to make it happen and don't care about the idea enough to implement it. More importantly your analysis indicates a damn good reasons not to implement it: the skills to make it happen are absent, a professional network containing people with those skills who are close enough to step onboard is absent; and the underlying business model is easy to replicate.

As for specific advice, I like this essay: https://sivers.org/multiply

Good luck.