As Paul Revere once warned, “The British [divas] are coming.” Estelle, a 28-year-old West Londoner, joins a burgeoning trans-Atlantic hit-parade cabal (Amy Winehouse, Leona Lewis), this one balancing expertly on the rapping-singing switchblade. Discovered by John Legend and crowned as the flagship artist on his fledgling Home School Records, Estelle turns Shine into a durable debut, pleasant and shrewd. Her big hit, “American Boy,” drags Kanye West on a domestic road trip through the valleys of California and the fragile psyches of American men, hospitably and acutely aware of America’s G-spot: vanity. More splendid moments abound: “Back in Love” and “In the Rain” are breathtaking trips into lovelorn melodrama. “So Much Out the Way” is spoiled by Wyclef Jean’s insoluble synths, but resurrected briefly by her semi-raps. Everything else she handles with aplomb, including the inevitable showdown with Legend himself (“You Are”); her slim, delightful pin-needle of a voice, though slight at first, is a reassuring constant over 47 minutes. As many have noted, Estelle recalls a specific pop luminary: Lauryn Hill, the fallen virtuoso of limitless promise and overwhelming demons. Shine revels in its creator’s limits, and avoids any demons deftly enough.