[sublynx]

I suppose that you are taking map contacts off SH3 from the realism settings. (There is a mod that takes all off, your sub, every contact, nothing gets marked on the map automatically). The SH3 setting is not that hardcore. It leaves the mark of your sub on the map and marks contact reports as they are radioed in. Sometimes there are single ships that get marked on the map automatically. The setting does not change that - they still get marked on the map. The hydrophone contacts get totally wiped out from the map. You do still get the ship closing or getting away assessment though.

I don't think the change really changes that much on the navigation map. You can make your own marks with relatively little effort. However I do feel that being hunted by escorts changes a lot. If there are many escorts you might have to keep your situational awareness updated by listening to the hydrophone yourself. If there are many ships around you, you might occasionally get totally lost about what's happening around you. It's like in a flight simulation - better not get in the middle of a furball if you want to have any understanding where the dangerous ones are. There's no god's eye view on the surroundings anymore.

It's definitely worth trying. If you don't find it fun, you can always go back.