I usually hunt just north of Ireland in AM52/AM53 early in the war. It's February 1940, and I'm just leaving from Wilhelmshaven for the 2nd Flotilla in a VIIB. Patrol number five.
I've only just discovered the delights of GWX and 100% realism, charting, plotting and intercepting targets properly. I also added a DiD rule to the game. Determined to survive the whole of the war with no reloads, this is where most of my fun is coming from.
I'm not sure what I'll be doing next. Probably looking for better hunting grounds as non stop Large Merchant/Medium Cargo/Coastal Vessel is getting a bit tedious. Some tankers would be nice, but I wonder if these are more prevelant later in the war.
Other than that, I have been offered the IX but turned it down in favour of keeping the VIIB.
For your game, how about a GWX3 DiD at 100%? Unless you do this already, or something harder
in which case I don't have any other suggestions. Med Flotilla maybe?
-Edit - VIIB not VIIC.