Wearstler has described her own design work, particularly her interior design for hotels, as "romantic" in style. Elle Decor wrote around 2015 that "Wearstler encapsulates contemporary sophistication and wit, with a nod to the past and a wink at the future. The mix is altogether her own and is tailored to every job." In 2008 she was deemed a "mega decorator" by Domino, with her hotel interiors described as reaching out to "the hip design public." "Wearstler was an early proponent of Midcentury Modern, decking out the Avalon Hotel in Beverly Hills in that style long before Mad Men hit the small screen. Her subsequent designs for hotels and homes epitomized the Hollywood Regency look that influenced pre-recession interiors for years. By the time Regency peaked, Wearstler had moved on, embracing the organic modernism of California studio artisans, such as ceramist Stan Bitters, and creating 1970s-inspired rooms that glimmered with metal and glass." — David A. Keeps for the Los Angeles Times (October 10, 2012) With a style periodically described as maximalism, she has been one of several designers credited with bringing "the decorative back to interior design" and mixing modern and historical designs. The New Yorker opined that since the late 1990s, "her style has evolved from mid-century modern to glammed-up Hollywood Regency to an ornate, layered look inspired in part by the late Hollywood set decorator and interior designer Tony Duquette. She uses intense colors, David Hicks-like graphic patterning, and contrasting textures (lacquer, parchment, shagreen)." In 2009 Dana Goodyear of The New Yorker dubbed Wearstler "the presiding grande dame of West Coast interior design," explaining that "Wearstler represents the uninhibited side of Los Angeles, the part that celebrates how far the city is from strict East Coast notions of good taste." Mayer Rus, the design and culture editor for Los Angeles Times Magazine, stated that "I think for many people around the world Kelly's work exemplifies this fantasy of beautiful sun-baked life, glamour in California. Kelly's genius is her ability to mix elements from all different eras, styles and periods. There's a certain bravery in what she does that flirts with going over-the-top, but always stands just back from the edge.