On Vic Mensa’s debut album, The Autobiography, the young Chicago rapper’s personal travails come sharply into view. He raps about his very public struggles with addiction, occasional troubles with the law, a complicated relationship with his hometown’s hip-hop scene, and stray thoughts about ending his life. Yet somehow, his musical identity lies just out of reach.That’s not surprising for a teenage prodigy whose first group, Kids These Days, was profiled in the New York Times when he was just finishing high school. The hip-hop/emo-pop band yielded many of the players who have driven the Windy City’s current renaissance, including trumpeter Nico Segal (a.k.a. Donnie Trumpet of The Social Experiment). Their rise preceded that of Chance the Rapper, who guested on the band’s EPs—and co-founded the SaveMoney crew with Mensa—before embarking on his own stellar career. But while Chance is now widely known as a good kid who connects a secular post-millennial generation with its spiritual potential, Vic has experimented as a solo artist, sometimes fitfully. His best single so far is arguably “Down on My Luck,” a terrific hip-house number from 2014. Like so many next-gen rappers, his work with electronic producers like Flume and Kaytranada is second nature, not a cross-genre gimmick. Yet he’s also tried to translate his industry buzz into songs with Kanye West (2015’s “U Mad”) and Gucci Mane (“What It Takes”), with little crossover success.Much of The Autobiography opts for an airy emo-rap sound typical of recent big-budget hip-hop like Logic’s Everybody and G-Eazy’s When It’s Dark Out. But Vic’s too sharp of a stylist to drown in the indistinct mainstream beats that mar some of his debut. He works real magic with Pharrell Williams and Saul Williams on “Wings,” and his collaboration with controversial South Side iconoclast Chief Keef on “Down 4 Some Ignorance (Ghetto Lullaby)” is long overdue. Then there are those diary-like lyrics, which range from comic tales like the Weezer-assisted “Homewrecker” to anguished meditations on blackness like “We Could Be Free.” Throughout, he remains an engaging performer, even if we’re not always sure where he’s leading us.