Hi Hans,
yes it would actually be fine if the voices of the crew would also include a 'free for surface' statement. But because the officers also work as navigators, they would plot any contact on the map so all you have to do before surfacing is looking at the map to see fit. This if you don't change the numerous game settings.
Looking at the map is not exactly the same of course, it takes longer, but it will work to tell you if it's safe to surface.
Also: If there are any contacts during their periscope check they would tell so with a message (Ship ID if known + bearing). That should mean: No message = Safe to surface.
Greetings
