[merc4ulfate]

If you want to add a real challenge to the game your should turn the auto targeting off and simply use manual targeting practices. You would not have to worry about colored lines nor arrow indicators in the scope you can fire when you are pleased with your own solution.

I do not even compute solutions any more. Most of the time I can line myself up so close that I can simply fire when the target is 10 degrees off zero and get hits. Even during the day I can normally get inside a convoy and fire from the stern and forward tubes at two ships simultaneously and wait for a second ship to cross my bow for another shot before having to dive to escape escorts. It helps greatly to have the German G7es homing torpedoes. Many times I allow the escorts to see me and then dive to lead them away from the convoy and then take them out first before attacking to the convoy itself with torpedoes and deck gun.

Some of the environmental mods increases the fog and therefore reduces surface distances where the AI's see you so being that I can control the deck gun myself I can see silhouettes in the fog where my AI crew members can not and use the deck gun without having the opposing vessel fire back. They simply can not see me. On my last patrol I took out 2/3's of the convoy this way after sinking all the escorts with the G7e's.