My autosave setting is 1 turn, meaning on every start of the turn the game is saved. I have two reasons for this.
1. I like the fact that I can decide to exit the game at every turn without the need to save myself.
2. It minimizes the loss in case of game crashes
I noticed the following problems with this:
1. Apparently if a shipyard has finished a ship and it should be launched at that turn, it does not get lauchned if you reload the autosave. Instead, the ship stays in orbit of the shipyard without any notification. I play bigger maps in many sessions over weeks and in the course of the games I sometimes find all kinds of ships in orbits of shipyards that should have been launched.
2. Apparently stuff like annexing of planets and other events happen after the autosave. That is somehow weird, because if you continue to play that event is part of that turn - but if you exit and continue by reloading the event might not happen or happen the next turn.
3. If the game crahes during the AI-turns, you lose all the work you did in your turn.
What I would like - and what would also fix the problems - is that the autosave function saves the game at the end of my turn. Meaning if I hit the turn-button, the first thing should be the saving of the game. That way, you wouldn't risk of losing your work because of AI-turn-crashes and the problems with save at that start are also eliminated. Also if I load the save, I can hit the turn button again or decide to do even more in that turn.