I must caution I only know segments of Kerouac's work. He does capture, fairly, that by the late 1950's the American frontier was nothing but an echo of what it once was, but beyond that, boomers who treat him as a demi-god run a tiresome treadmill. The narrative voice can hold your attention, but seems to hover between Hemingway's immediacy and Woolf's stream of consciousness, burning out before it ever hit full throttle.
On The Road isn't a bad book necessarily, just a styled period piece. As a writer Jack pretty much flared out after that.
I would pick Annie Proulx, which I know isn't fair, since she is a successful contemporary, but Amazon has over 1000 owners of The Shipping News who are seemingly eager to be divested of the title--and I don't see her attempts at regionalized humor as very original.

