Saving movement that you've done without ending turn would be really useful for large maps with 100s of cities in casual games.
I've just had a pleasant experience: WWIII Embers of War, having 300 cities and 3k units a turn lasts for hours depending on how engaged you are. I've spent about 2 hours in it, taking my time, chilling, and when i was doing some polishing end movements and shopping, 2 minutes before ending turn a window popped up saying connection lost, reload or lobby. It is not hard to imagine how i felt.
Even in general you have to find a couple of continous hours to make your move, which is not too easy and certainly not 'casual'. Of course one way is to not play on large maps but hey.
So saving movements during turn would be reallLLLllly important, and it can't be too hard to implement. Thank you.