This is more like a 3.5 for me, but I'm rounding up.
In some ways, I think the format of the graphic novel is somewhat limiting to the subject matter, since it involves issues of race and identity, and what it means to be of mixed ethnicity--which is some rather complicated stuff to convey with simple line drawings, dialog and occasional narrative.
The main character, Carla, has grown up in the U.S., always speaking English and only English, but moves to Mexico City and gets caught up in trying to live an 'authentic Mexican' life there. Unfortunately, her means of doing this is to fall in with the first group who will have her. And while several members of this new cluster of friends rail against tourists, whites, capitalism, and the United States, they seem to connect to Carla exactly because that is what she represents--and because they think she may provide them some advantage from her ties to the United States and the world of privilege. But they are fooling themselves just as much as Carla is fooling herself about her ability to become Mexican--or even half-Mexican--by rejecting some of the more obvious connections to the world of the expats.
So characters like Memo attempt to impress Carla by inviting her along on 'authentic' excursions which he admits to his friends are only meant to impress gullible American women. And Oscar, who becomes Carla's boyfriend, seems to be perpetually bugging her for money (which she doesn't have) or to connect him to Americans who can further his DJ career--a career he never really pursues in any meaningful way. Carla believes she is finding herself, but is mostly just drifting. Her story could be like that of many people in their early to mid-20s, running around to parties, not having any real direction, and making plenty of bad choices--she just chooses to do it in a city that is foreign to her.
I was somewhat disappointed with what occurred in the final act--it seemed a bit too easy to go that direction, especially when, up to that point the entire story had been more about relationships and connections between people. Although looking back I realize that Abel was leading up to that kind of conclusion, I think I had been blinding myself to it, in the hopes of a more 'down to earth' end to the story.
Still, there is plenty of good material here, and it's easy to identify with much of it, and the misguided decisions Carla and those around her make. For instance, it's very telling when, near the end of the story, Carla realizes she never even bothered to look up the village where her father's family came from, or made any effort to track down any of her blood relatives. There were ways for her to connect with (half) her roots, but she left those paths unexplored.