Thanks for posting the discussion thread, B Munro. Meanwhile, I'm going to update our list with some of the newer suggestions that have been proposed thus far.
1. Bring The Jubilee (Confederate victory at Gettysburg leads to them winning the American Civil War and gaining their independence. Because of massive war reparations being imposed on the rump U.S., the Confederate States become a prosperous world power, while the United States decline into drudgery and poverty)
2. Agent Of Byzantium (series of espionage thrillers set in a world where Islam was never founded and the Byzantine Empire never fell. The Byzantine Empire remains the dominant power of Europe, and remains in a cold war with the Persian Empire)
3. Guns Of The South (time-travelers from OTL early 21st Century equip Robert E. Lee's Army of Northern Virginia with AK-47 assault rifles, helping them turn the tide of the American Civil War and win independence. But the time-travelers have an agenda of their own, leading to a battle for the heart and soul of the newborn Confederate States of America)
4. For Want Of A Nail (British victory at Saratoga leads to the defeat of the American Revolution. To restore peace and tranquility, Britain reforms the post-war American colonies into the semi-autonomous, yet still loyal to the British crown, Confederation of North America. Meanwhile, the unreconstructed American revolutionaries flee westward, take over Mexico, and form their own republic, the United States of Mexico, leading to a whole new balance of power in the North American continent)
5. Dominion (espionage thriller set in a world where Lord Halifax becomes Prime Minister instead of Churchill in 1940, leading to Britain making peace with Nazi Germany after Dunkirk. In ATL 1952, war between Germany and the Soviet Union continues to rage, while Britain inches its way toward Nazism itself)
6. Pavane (series of stories set in a world where Protestantism was destroyed following the assassination of Queen Elizabeth, and the Roman Catholic Church regained complete dominance over Europe)
7. Lest Darkness Fall (an American archeologist from OTL 1930's is ISOT'd back to the 6th Century, during the reign of the Ostrogothic Kingdom over the remnants of the Western Roman Empire. With the Byzantine forces on their way to try to conquer Italy, he sets out to use his knowledge to save Roman civilization from its ultimate collapse)
8. Ruled Britannia (the Spanish Armada conquers England in 1588. Queen Elizabeth is imprisoned, the English are converted back to Catholicism at swordpoint, and an inquisition even more merciless than its original Spanish counterpart roots out treason and heresy. William Shakespeare is approached by the English underground to write a play that will inspire the English people to revolt, but the Spanish occupying authorities also approach him and ask him to write a play glorifying King Phillip II and solidifying Spain's rule over England. A deadly game of cat and mouse ensues).
9. Wake Up and Dream (Clark Gable is an out-of-work actor, his movie career ended by the rise of a new cinematic technology called "feelies," which not only capture images and sounds, but project actual feelings, emotions, and sensations into audiences. In ATL 1940, working as a private investigator in Los Angeles, while a growing American fascist party is arising, challenging FDR, and pushing the U.S. into collusion with Hitler, a seemingly simple job leads to an attempt on his life, and a conspiracy that spreads throughout the underbelly of Hollywood)
10. When Angels Wept: A What-If History of the Cuban Missile Crisis (ATL nonfiction book detailing the history of the worst case scenario occurring in October 1962: global nuclear war erupting over the Cuban Missile Crisis, including the history behind it, how it unfolded, and how the world tried to adapt in its aftermath)
11. Then Everything Changed: Stunning Alternate Histories of American Politics (three stories of changes in Cold War-era American politics and consequences that follow: John F. Kennedy is assassinated in December 1960, leading to an early Lyndon Johnson presidency; Robert F. Kennedy survives his assassination and is elected in 1968; and Gerald R. Ford is reelected in 1976)
12. The Severed Wing (two PODs: Theodore Roosevelt is elected to the U.S. presidency in 1912, and French socialist movement leader Jean Jaures survives his assassination. Under TR's leadership, the United States joins World War I on the Entente's side much sooner, bringing about a faster Entente victory and imposing a reasonable, balance-of-power-restoring peace on Germany. Jaures, meanwhile, succeeds in unifying Europe's various socialist movements into cooperating with each other across national lines. The 20th Century is restored to peace after the brief flare-up of the Great War, creating a world with no Great Depression, World War II, or Holocaust, but, in turn, no discrediting of imperialism, racism, and anti-Semitism either).
13. Fatherland (everything goes right for Nazi Germany in World War II, allowing them to defeat both Britain the USSR. The United States defeats Japan in the Pacific theater, but Germany is victorious in Europe. This leads to a Cold War between America and the Greater German Reich, which is the dominant superpower of Eurasia, forcing western Europe into its sphere of influence and carrying out Generalplan Ost on Russia. In ATL 1964, as the Reich celebrates Hitler's 75th birthday and pursues a policy of détente with the U.S., an SS kriminalpolizei detective investigates the murder of an elderly Nazi official that is but the tip of the iceberg to sinister secrets and conspiracies).
14. SS-GB (detective story set after Nazi Germany successfully invades and occupies Britain in 1941. A Scotland Yard homicide detective, working under the authority of the British branch of the SS, investigates a mysterious murder in London that leads to a dark web of intrigue that combines the internal politics of Nazi-dominated Britain, the British resistance movement, and international geopolitics)
15. The Difference Engine (one of the most influential novels of the steampunk genre. Charles Babbage perfects his Difference Engine in 1824, followed up by his development of the Analytical Engine, an early, fully functional computer system. The Information Age dawns over a century early, and Victorian Britain leads the way as industry and information technology develop by unprecedented leaps and bounds, and the British Empire solidifies its position as the unquestioned dominant power on Earth. At home, meanwhile, British society undergoes a lot of changes itself, some of it positive, others more turbulent).