Would be nice if player structures and landscape changes showed up on the map because I have loads of canals and a fairly sizable fort that I'd like to be able to see without cluttering my map with labelled markers. Would also help if minor modifications I make to the landscape showed up because I'm sure we all forget about our little projects once in a while and it can lead to ship damage and significant route re-planning. I know it's not going to be super detailed but if I dig a huge canal, I'd at least like to see the gap in the land and I'd like to see my fort as a brownish smudge.
I'm sure I can't be the first to bring this up.