Hamilton's novels are filled with drinking, murder, madness, unrequited passion, loneliness, casual cruelty, the anomie of modern society, dismal, drenching weather, and humor — the words "black comedy" spring to mind. The two I've read are imbued with a decidedly noirish sensibility. Still, Hamilton has been compared with both Charles Dickens and Jane Austen — strange bedfellows, if I may put it so indelicately, and neither exactly the first name in noir. But there is truth there: Hamilton's characters, like Dickens's, are almost surreal products of the distorting forces of their society: They are the peculiar spawn of the modern age, sometimes predators, sometimes unhardy shoots of humanity deprived of sun, their promise stifled. And both writers see kindness as the highest virtue. As for his similarity to Austen: His portrayal of how manners and social relationships are integral to identity are akin to hers, as is the wickedness with which he dissects social situations. And, while we're at it, I, personally, would like to compare him with Barbara Pym in his bleak, biting wit and interest in the rotten deal given to quietly decent people of reduced means.
Katherine A Powers takes a particular look at 2 relatively recent reissues (that I myself read not so long ago): Hangover Square — "It makes personal an atmosphere of deluded, cheap relief, of irresolution; and conveys all the crumminess of the sense of escape bought by a couple of stiff ones at mid day." — and The Slaves of Solitude — "I enjoyed every page of this novel, and have never had the pleasure of seeing the panoply of loneliness and depression employed to such brilliant comic effect."