In a recent “Vanity Fair” profile, six-time Tony Award winner Audra McDonald named her current role of Suzanne Alexander in Broadway’s “Ohio State Murders” as the hardest to date. Suzanne is a semi-autobiographical stand-in for the show’s 91-year-old playwright Adrienne Kennedy, who actually graduated from the gapingly large research university in 1953. Suzanne inhabits four of Kennedy’s dramas — a cycle called The Alexander Plays — and consistently envelops readers in her hypnotic (and oft manic) psyche. “Ohio” is number two in the series; Kennedy first penned the haunting memory play in 1992. Those three decades have brought us closer to, but nowhere near the true measure of labyrinthine brilliance overflowing from Kennedy’s mind. Hopefully, the next three can. And even though Kenny Leon’s plain direction threatens to flatten the rocky beauty of “Ohio,” this production ultimately reaffirms Kennedy’s singular mastery of common language, dissolution of traditional form and rightful place on Broadway.