1) What If? 2: Eminent Historians Imagine What Might Have Been, ed. Robert Cowley
A competent collection of essays on counterfactual history. The best is the one proposing the death of Charles I and his children in an outbreak of plague in 1641; the British throne would then have passed to his cousin Elizabeth, better known to history as the Winter Queen, who would have been more politically astute (Charles I tends to get a poor write-up) and would have managed the late 17th century British Isles much better though to the impoverishment of political thought. The author left out the important Irish dimension though. Another promising one about Napoleon’s plans for North America didn’t really chase the scenario as much as I wanted it to. I’ve also never been very convinced by the “Harold wins in 1066” scenario, given how Normanised 11th-century England already was. And the last essay, about the importance of the potato, really missed the point of the whole book by not putting forward an alternative path of history.
Coming to this late, but have just finished the short stories. I broadly agree with your comments, though I may order the stories differently. In some ways Amaryllis was the bet written story, but apart from the fertility restrictions, it could just as easily have been written as a non-SF story.