"I can't think of any novel offhand which involves people working in the middle or lower rungs of a company."

John Sladek (before his untimely death) staked out that territory. (Which admittedly goes to underscore your point.)

One of the items on my to-do list is pretty much such a novel, although arguably it's horror or mainstream rather than SF. (Not to mention semi-autobiographical.) Ah well.