Honestly I make far and away the most money from shipwrecks, I never see other ships bother with them yet I'm constantly finding them all over the place generally with spice and tea chests, some higher end skulls, captains chests etc. I mean there's some ships that have bunk goods but in general they're good.
The last ship I visited netted me over 4,000 gold and it was maybe a 30 second voyage from an outpost. No searching, no fighting, barely any effort and you cash in.
