What does that mean? "Change the dynamic," how?
Kirk vs. Spock in this timeline. Maybe set up a new Romulan war. Instead of the Romulans creating the cloaking device, have the Federation do it first. Which leads Spock to have a crisis of conscious and defecting to the Romulan side, with the cloaking device.
Kirk feels betrayed by his former friend. Taking on a Sisko-like hunt for him through the Romulan Empire.