[TorpX]

I think the problem with what you want, is that if anything is plotted on the map by the game, it is 100% accurate, to the nearest pixel. This applies to the 'tails' of the symbols, too. So, if the mod/options put these on the map, they tend to give away the game.

Playing RFB + RSRDC (without map contacts), I sometimes get radio messages about contacts. These give a certain amount of information about position, course, and speed, but I have no way of knowing if it is accurate, or not. Of course, I must plot these myself, if I want to pursue them. This makes them much more of a gamble.

I think it is worthwhile to point out that most sinkings were the result of targets of opportunity. Sometimes info from decryption intel was sent to subs, but even then the odds were against an interception. It was only late in the war, when we had many subs working a smaller area of ocean, and better intel, that the chasing of contact reports really paid off.