Nahant looks nice, but be warned, I could not find one spot where an outsider can park for an extended period of time. In fact the only parking I found that wasn't "Resident Only" was in front of the library, which was limited to 30 minutes parking.
On the other side of the bay from Nahant is Revere Beach; much easier to park, some nice scenery to be found.
https://www.flickr.com/search/?w=88929764@N00&q=revere
If you're into landscape / seascape photography and know where you will be (e.g., Lynn, MA), I highly recommend what I do: go on Google Maps, turn on Satellite view, and just look for potentially cool spots (you can turn on Explore and see photos taken near the area).