A review in Performing Songwriter magazine described the characters found in Gravitational Forces as "everyday people pulled, led, and sometimes dragged by some outside strength.

The songs on the album that Keen did not write range from Johnny Cash's often-covered classic, "I Still Miss Someone" to Townes Van Zandt's more obscure "Snowin' on Raton".

Keen and his band also cover the traditional blues, "Walkin' Cane" in what has been described as a "rowdy, back-porch take,"[14] and treat Terry Allen's "High Plains Jamboree" with a backdrop of "bar room party sounds.

"[17] The cover that reviewers most recognize as a choice pick to match Keen and his career outside of mainstream music is Joe Dolce's "Hall of Fame".

"Wild Wind" is a harmonica-heavy minor key introduction to a series of tragic small-town characters, that will leave some listeners wanting to know more.

[19] Keen's "Goin' Nowhere Blues" has been described as "chilling"[7] and contains references to Langston Hughes, Woody Guthrie, Martin Luther King Jr., Cesar Chavez, and down-and-out union workers.

Keen delivers a spoken stream of consciousness on the "temporal distortion of a four-hour soundcheck,"[3] complete with a free jazz accompaniment that caused one reviewer to liken it to Allen Ginsberg's reading of "Howl" backed by the Kronos Quartet.