Ok, ok, we hear you: enough of the dark themes already. Here’s one that should help set the universe back into balance: The Journalist by Lucian Marin. It’s a crisp, professional, black-on-white theme designed for serious writers.
The Journalist features a fixed-width, two-column layout, elegant typography for post text and block quotes, and supports widgets in the right-hand sidebar. Look for it on page 4 of your Presentation / Themes tab (under “T” for “The”).