For realism ( I only play 76%, I like the external views
). Things like, avoid reloading extrernal torpedos too close to enemy coasts or high traffic shipping lanes. Even if it means burning up fuel to find a more remote sea area, it feels better. Bringing in externals whilst tailing a convoy with the RL risk of escorts dropping back to patrol the rear, feels like a cheat-around. Of course in the later war years, reloading externals becomes impossible anyway.
Engine speed doen't affect battery recharge time, as far as I know. So don't waste fuel thinking you are recharging more quickly by increasing speed.
For rough seas. Set the speed by the knots rather than just the telegraph setting (1/3-1/2 or Full etc) If I hit rough weather, for example and I am at 8 knots, the speed will drop to about 6 or 7 knots. But the maximum range at 'set speed for 8 knots' will still be greater than 8 knots at telegraph 1/3, which would normaly be about 10 or 11 knots in calm seas. If that makes any sense
