Overall very nice map. I think the others covered most of the most obvious items that stand out to me. Here's a few remaining details:
1)bathymetry color breaks are labeled with each new break beginning with the ending value of the last break (50 - 100 & 100 - 150). not sure how this works for physical breaks like this but it would be incorrect for thematic or statistical breaks. Look into how this is represented on other maps.
2) fragmented county boundary lines. The boundaries probably connect in the open water but you only show partial extents with lines ending abruptly for no obvious reason.
3)Grid labels. It's hard to tell at this resolution but I'm guessing this is UTM? If so I'm not sure it's conventionally labeled (see https://www.e-education.psu.edu/files/geog4...map_corner.jpg
). The label orientation is odd as well. I would either place each coordinate label horizontally in the plane of normal reading, or parallel to the line of its grid line so that reading the label points your eye along the grid path.
4) remove halos where possible, especially the water labels. You might beef up the type size for the atlantic ocean label and stretch it out a long a curved path.
5) the scale and N arrow group is in a busy spot on the map with lots of bathymetry areas behind it. There's a quieter spot just to its right that might work better.
Take all of this with a grain of salt as it's difficult to really be sure of what I'm seeing without a full res version.