How do I make sure my essay topic does not come off generic or repetitive?

When I began brainstorming different college essay topics I quickly became attached to the idea of talking about Legos and my childhood obsession with them. However, I didn't learn until recently how common this topic might be. I understand that a lot of students planning to major in engineering tend to write this type of essay. I plan on majoring in finance or another business related field so I don't think that the topic will seem "repetitive" for someone with my interests. But, I just wanted some thoughts from others on the topic.

Also just so that you have a better idea of what I decided to talk about in the essay, I have begun writing about Legos and how they helped me become comfortable with the idea of uncertainty in my own life.