Here’s an excellent review of All Men of Genius by Sofia Samatar on the Strange Horizons website.
In her review Sofia sums the story up (which I did not do, sorry) without giving anything away (that in itself is a talent). She explores the interest of the novel’s secondary characters, especially Cecily’s governess, Miriam Isaacs, and relates this well to Rosen’s interest in the minor or individual stories and plots of his novel rather than the larger events, or meta-issues of politics or gender-roles. The review is worth reading for that discussion alone. She also writes about the problem of the one-dimensional antagonist, Volio. And wow, Sofia sums it all up nicely – look at that last sentence! Tight, evocative, and light.