[Hitman]

As for the stationary subs in the wolfpack, I wonder if it would be possible to spawn them with an order to set speed to 7 knots or so (surfaced, less if submerged) so they would move even if in a simple straight line.

As I already suggested, you also could make the model invisible and then the AI would not shoot at it but only drop DCs (They will not shoot with guns if they only have hydrophone contact). And finally, make it dissapear after a while, to simulate the chance of escaping - less in late war.

In all, seeing the hydrophone lines i not that bad, as realistically you could have contact with other uboats, but f you spawn them submerged then I would suggest reducing the noise level a lot, so that both the player rarely contacts them (As in real life) and the scorts have a harder time finding them.