The historical campaign off the coast of Norway in 1940 is definently my favourite GWX events. Troops landing north of Narvik, and also in the area of Åndalsnes(a bit south of Trondheim) allows for opportunities to get up close and personall with several troop ships. The roaming Carrier Illustrious Task Force is also very possible to track down, due to frequent reports from Luftwaffe and other subs.
In my last campaign (with the patrol starting around 1 April) I assigned myself a patrol grid off Norway, and around the 15th or so, after crusing back and forth dodging enemy task forces, I got a report of a huge task force heading my way. I guestimated the course, went to PD and waited for three hours or so. And there, Lo and behold, the Illustrious, two hvy crusier and a dozen destroyers roamed into view. It was around midnight and stormy weather, but with some carefull manuevering I managed to get into firing positions and slammed four torpedoes into the Illustrious. Beautifull
On my way back to Germany I got a report saying help needed at Åndalsnes. I went there and three troop transports escorted by about five or six destroyers. I held my distance and popped up to deliver a contact report and a hour or so later a horde of Ju 87's came screaming in, sinking all but one transport and a destroyer. I tehn sank the transport with my two last torpedoes, and went home quite content. Alll in all, the best SH III experience I ever had.