When I started my applications, I had no idea what admissions committees would look for in an SOP, so I enlisted the help of a very kind professor from undergrad to literally go through draft after draft with me. If you happen to have a professor willing to do this with you, definitely do it!
The SOP: After summarizing my undergrad work, professional experience, and research experience, I went on to describe my honors thesis in detail. Then I outlined some themes from that paper that I would like to continue to explore in grad school. I also connected these themes to a seminar paper or two, to show consistency in my interests. I didn't propose any specific topics or artists for further research, just the themes and subfield.
I really hope you don't have to go through this again, but if that was at all helpful, feel free to PM me (anyone), and I can go into more detail. Good luck georgica!