I find the mission objectives too easy

.
Sink 5 escort ships? That's for pussies. How about "sink 1 battleship and her 8 escorts". Because that's what I did on my last patrol
What I find annoying however is that a few months into the war, I only need to sink 1 ship around the patrol area and then
"MISSION ACCOMPLISHED! Come back to Base.. We miss you already."