Atm its back to SH3 cause of the new compartments mods - engine room and crew quarters.
SH4 awesome but one thing that has always annoyed me is not being able to zap back to base like in SH3 instead we have to sail all the way back which is a long trip, it takes long enough to get to your patrol point. I would rather waste fuel hunting then when there's all but a drop left, i can return to base with a click of the button.