My three people of note to choose from are Titus Salt, Amelia Earhart, and Nikola Tesla. I'm already quite sure I won't be focusing on Mr Salt, just because I was lucky to get the iconic Earhart and Tesla, both of whom are both much more interesting to me. (No disrespect to Titus).
I find Amelia Earhart incredibly interesting ironically for everything we don't know about her instead of everything we do. I focused on some of the theories surrounding her disappearance/death as most of them are probably bizarre enough to fuel a brief on their own. There is a lot of interesting material I'd like to learn more about, especially her almost storybook style adventurous nature and progressive thinking. Both Tesla and Earhart are enigmatic figures in death, as they both lived lives very much in the public eye but then died very much alone. The sheer lack of knowledge surrounding Amelia Earhart fascinates me, as it illustrates the difference in society, how it feels like someone is always keeping tabs on everyone today, but in her time a famed pilot could go missing and literally vanish forever. While there are rumours about her disappearance and where her plane (which by the way has the greatest lady plane name ever - The Lockheed Electra), everyone who ever went looking for her is dead now and so is she, so it interests me even more as its a mystery we will probably never get the answer to. Unless the Bermuda Triangle does turn out to be some mad portal and she's waiting for us in 2067. Which would be a great source for a brief.
When I started researching these people I couldn't decide between Tesla and Earhart, but the more reading I've done about both I've found a lot more material I'm interested in for Tesla. He died alone in a hotel room and what was left of his work was seized by the American government and never referenced again. That alone sounds like the start of a 90s comic book. The fact that he lived a life of intellectual discovery and exploration and then in death became an enigma and a mystery is something I really want to explore further, so I think Tesla will be the person of note I choose to pursue. Science bitch!