It is also dotted with green areas, however not in the same way as Portland. Instead of massive parks, Boston has several smaller green zones sprinkled around the city, therefore they don't impede travel by car. The bridges are perfect for district boundaries as seen in GTA III, San Andreas and IV. There is enough variation between districts for Rockstar to create several areas with their own atmosphere, making the world feel sufficiently expansive. The city has earned the nickname "City of Neighborhoods" seeing as there are over 23, varied and diverse such areas officially designated.
Crime
"Unfortunately", the extremely well coordinated cooperation between the Boston PD, the District Attorney and the neighborhood watch groups has managed to lower the crime rate in the city drastically. In 2015, there were a total of 39 homicides in the city.
Recognition
Boston is as strong in this regard as D.C., pretty much. With countless historical sites related to the American Revolution — kind of a big thing, seeing as it lead to the country existing — result in countless landmarks to be found even in the downtown area.
Besides the historical landmarks, the city is filled with more recent structures of note. The Boston City Hall is one of the most well known examples of brutalist architecture and an extremely imposing and iconic building. Boston also has its fair share of stadiums, such as the home field of the legendary Red Sox baseball team.
Boston is home to several world-famous universities and schools, each of which have well known and recognizable buildings which could be adapted for the game's map.
Potential Story
Seeing as GTA is grounded in modern (or at the very least 80's) setting, it would be hard to capitalize on the rich history of the city. Plus, Assassin's Creed III already did that, and being associated with that particular installment of the franchise may not be the best marketing.
Even if not a whole story concept, it would be fun to see PAX weaved into the game somehow. At some point in the story a gaming convention (with a sufficiently satirical, Rockstar-style name) would take place in the city and the player's target would be somewhere on the grounds. However, the target is cosplaying as a popular character, so he/she isn't the only one dressed like that. The player must also wear a costume to smuggle in a weapon. You'd then need to find the target during the convention, with all kinds of shenanigans like fans wanting to take pictures with you and the like.
Either that, or the game could focus on a new gang rising in town who are obsessed with references to the American Revolution and think that it's time for another one. The player is the leader/member of another gang who at first simply oppose the "revolutionaries" but are later drawn into a stupidly convoluted conspiracy situation with them trying to overthrow the government. However, that isn't very "GTA".
Final Verdict:
B
Pros: Beneficial geography, variety, recognition.
Cons: Low crime, not too great story potential.
As a city, Boston may make a great open world game map, but as a setting for GTA, it may not be the best fit. If Rockstar comes up with a good enough story that isn't particularly tied to the city and is liberal with the crime levels, Boston could work well. However if they try to stay true to what the city is like, the game would be a tad too peaceful for GTA. While the city is nicely varied and littered with landmarks, it has a lot more potential for historical stories.
Would you like to see a GTA game set in Boston? What other city would you suggest for evaluation?