PHILADELPHIA — There’s nothing like a festival of new plays to show how hard it is to write a really good one. But that’s arguably the most notable outcome of the inaugural Philadelphia New Play Festival: Where Theater Begins, a heroic citywide effort that ran Feb. 8-18, opening nine new shows in 10 days.Defying logical expectations, the most engaging entertainment came from Vagabond Acting Troupe’s “The Wedding Consultant,” staged on the second floor of a restaurant, with borrowed lights, terrible sightlines and uncomfortable folding chairs for the audience. The unambitious solo show was far more satisfying than other ventures with major production resources behind them. Eric Singel — who wrote and performed — makes a case for legalizing gay marriage by creating a funny and complicated plot involving many characters (grooms, mothers of grooms, their lovers, etc.), many accents and many costumes — and a happy ending engineered by the unflappable wedding consultant, who knows that “one wedding is just like another when you get down to it.” InterAct Theater’s “A House With No Walls” also takes up a topical issue and is likely to have a life in the regionals. In this, the third of his “race trilogy,” Thomas Gibbons tackles another controversy inspired by current events about two powerful African-Americans who clash over the site of a new museum to be built on slave quarters at George Washington’s Philadelphia home. But despite its hot-button issues, the effect is more like a living-history museum show than real drama, with characters — a glamorous black neo-con vs. an old-time rabble-rousing scammer, both manipulating a white Jewish intellectual too blatantly — sounding more like tools of the playwright’s debate than human beings. Ultra-contemporary in subject if not style is Philadelphia Theater Company’s “Nerds://A Musical Software Satire,” possibly the entry highest on commercial producers’ radars. Show is a lively musical comedy about the history of computers, featuring Steve Jobs (portrayed as a no-talent womanizer) and Bill Gates (portrayed as a megalomaniac) in a high-tech throwdown to overcome their nerddom. Energetic and sophomoric, with mainstream, forgettable music and only the occasional clever lyric, this is really an afterschool special, with a moral at the end: Don’t bully nerds; they may turn out to be billionaires. The rest of the fest was a series of backward glances, including an adaptation from People’s Light & Theater Company of beloved children’s book “Anne of Green Gables” and an unsuccessful stage reworking of Isaac Bashevis Singer’s novel “Enemies: A Love Story” from the Wilma Theater Company. In this story of a Holocaust survivor with three wives in 1949 New York, Singer asks, with his well-known tragicomic irony, if it’s possible to recover from having survived. But interesting questions are generally unsuited to soap opera, which is what this play is — slow, repetitious, over-explained and dramatically inert. Walnut Independence Studio’s “Bookends” is more a rip-off than an adaptation. M.J. Feely’s play concerns a famous playwright and a famous director whose friendship hits the skids after interrogation by the House Un-American Activities Committee. (Gosh, I wonder who they could be?) Years later, the two meet again for an old-lefty showdown. It’s one thing to write a biodrama; it’s another to appropriate a playwright’s biography, rename the characters and pretend they’re fictional. It’s even worse to reduce the well-known life to trite sentimentality. Arthur Miller, were he alive, would be within his rights to sue for defamation by drivel. Similarly focused on the past are the two characters of “Dex and Julie Sittin’ in a Tree.” Bruce Graham’s latest is about college sweethearts who meet years later, a reunion pivoting on the predictable plot twist of a never-before-revealed pregnancy. With two unlikable characters locked in a nasty verbal duel, this is a cheesy sitcom turned dark. Graham makes another appearance, with playwrights Michael Hollinger and Arden Kass in five one-acts about loneliness that comprise “Hearts and Soles.” Character is sacrificed to caricature and plot to situation, while the dialogue sounds lifted from letters to advice columns from the lovelorn and/or sex-starved. That life is lonely and difficult for single thirtysomethings is old news. Funniest piece is Hollinger’s “Truth Decay,” in which two phobics meet cute in a hotel; their fears turn out to be wildly complementary if not compatible, and the title turns out to be the evening’s wittiest moment. “Stormy Weather: Imagining Lena Horne” at the Prince Music Theater is another biodrama and a terrific show — not because Sharleen Cooper Cohen’s book is much more than a stock rags-to-riches saga, but because it’s full of brilliant songs. It also has an underused but radiant Leslie Uggams who recreates Horne’s legendary vocals but unfortunately shares thrush duties with a “young Lena.” In addition to the title song, the show includes “That Old Feeling,” “Stardust,” “There’ll Be Some Changes Made” and “From This Moment On” — and that’s just a sampling. Given the absence elsewhere in the fest of great theatrical storytelling, those classics of the American songbook cast a powerful spell.