I would suggest "In the Mothers’ Land" from Élisabeth Vonarburg. It also talk about alternate society centered around gender. I didnt really liked the left hand of the night, but liked that one. And LeGuin saluted the book apparently too.
When working with kanban I maintained a average number of card done per days. if someone asked when some card woud be done, I just multiplied the number of card ahead of that one by average and get an estimate. You can estimate the cards but usually it doesnt really improve accuracy as tasks are on average the same size.