In recent musicals, hyperdesign is outstripping writing and direction for clarity, expressiveness and excitement.When Bobbie’s balloons are more fascinating than she is, your production of “Company” has a serious problem.I’m speaking of the inflatable Mylar numerals that, in the current Broadway revival of the Stephen Sondheim-George Furth musical, keep drawing the eye away from the main character as she is feted by friends on her 35th birthday.Those balloons — stand-ins for Bobbie’s disappearing youth — aren’t the only scene stealers. Bunny Christie’s ingenious design for the revival is filled with visual gimmicks that in representing the production’s themes keep crowding out the characters.During the song “Another Hundred People” — a barbed tribute to the missed connections of urbanity — large neon letters that spell the show’s title start wandering about the stage, as if stalking the cast. Eventually, three of the letters regroup to spell “NYC”: a neatly made point, though I couldn’t help wondering what happened to the other four.Then there’s the warren of interconnected spaces, some joined by trap doors, that paints Bobbie’s path to companionship as a cross between Alice in Wonderland and Chutes and Ladders.But for all the cleverness of Christie’s designs, they don’t so much nourish Marianne Elliott’s production as overwrite it, filling its many dramatic holes with eye candy.That’s no news on Broadway, which never met a conceptual problem it couldn’t attack with confetti cannons and other weapons of what we might call hyperdesign. Spectacular effects are part of the brand, and when used smartly can both thrill and inform.Yet, looking back at the shows that have opened or reopened in the last few months, it seems to me that designers, bringing evermore astonishing prowess to bear, too often outshine the work they are meant to support. As if to compensate, the stories are getting dimmer; their beautiful rooms, to paraphrase Kafka, are empty.In “Diana, the Musical,” Buckingham Palace was thinly suggested by some electric bulb tracery.Sara Krulwich/The New York TimesTake “Diana, the Musical,” which I won’t rake over the coals again except to say it was phony from first to last. (It closed, after just 49 performances and previews, on Dec. 19.) Nor were its sets especially assertive: Buckingham Palace and other locations were thinly suggested by some electric bulb tracery.But apparently having decided that what audiences would want most from a fantasia on the life of the People’s Princess is a jaw-dropping parade of extravagant costumes, the producers budgeted accordingly. The 38 outfits designed for Diana by William Ivey Long dramatized how she transformed herself from kindergarten teacher to royal frump to executive princess to international fashion plate far better than the writers did.No wonder those dresses — and the quick-change artistry that in one scene allowed her to change them six times — won applause. Unfortunately, in the process, the character herself was rendered about as expressive as a clothes hanger. That was almost literally so in her wedding scene, as Jeanna de Waal, who played Diana, disappeared inside a gown built like a cage.A clever enough metaphor, but why was the costume design forced to do so much work that the story should have done itself?The problem is even more evident in Lincoln Center Theater’s production of “Flying Over Sunset,” though it is a far more interesting musical. In Act II, its book, by James Lapine, imagines a weekend at the end of the 1950s during which Cary Grant, Aldous Huxley and Clare Boothe Luce experiment with LSD simultaneously. Their hallucinations are meant to address the unresolved conflicts carefully set up in Act I.But how do you dramatize a hallucination? Even if you can describe it in words, it will never be as interesting to those not tripping as it is to those who are.How do you dramatize a hallucination?“Flying Over Sunset,” starring, from left, Robert Sella, Harry Hadden-Paton, Carmen Cusack and Tony Yazbeck, tries to pull it off with psychedelic light and sound design.Sara Krulwich/The New York TimesLapine’s book does not overcome that obstacle, but as the director, he has been able to assemble a team of designers who at least get close. In this case, it is not the set or costumes doing the heavy lifting so much as the lighting (by Bradley King) and projections (by 59 Productions) working in concert with the sound design (by Dan Moses Schreier). In their hands, psychedelic imagery, amplified footfalls and intensely colored light become a trip in themselves, peeling away the skin of everyday life to reveal a richer world inside.It’s not a real solution, though; the often-beautiful imagery has the side effect of making ordinary perception, unenhanced by pharmaceuticals, seem banal. As soon as the characters talk, the illusion of richness evaporates. If it’s arguable whether the trips change the characters, as Lapine posits, it’s certain that they do not change us.“Flying Over Sunset” left me trying to decide whether muscular design takes over because the ideas are too frail or the ideas retreat because design hogs all the attention. Either way, it’s a predictable problem, and some productions have developed workarounds. “Moulin Rouge! The Musical,” for instance, is smart enough to keep dialogue to a minimum as it inundates the theater with sound and color. If it ever lets the audience come up for air, the silliness of the story might be revealed as the wrong kind of distraction.Which is not to say there’s a right kind of distraction. A show with enough on its mind, with a minimum of muddles and longueurs, doesn’t require bombarding with extraneous sensory excitement. That doesn’t mean it should be visually dull, even if for economic reasons that’s often the case.Take “Kimberly Akimbo,” one of the finest and most feelingful new musicals of 2021, with music by Jeanine Tesori and words by David Lindsay-Abaire, based on his 2000 play. The Atlantic Theater production might have been even better with a more exciting design to support those feelings and a bigger frame to set off the prodigious performance by Victoria Clark as a teenager who ages too quickly. Perhaps we’ll have the chance to find out, if the show, which is scheduled to close on Jan. 15, transfers to Broadway in the new year.“Kimberly Akimbo” might have been even better with a more exciting set design to support the wonderful performances by Victoria Clark, left, and Justin Cooley.Sara Krulwich/The New York TimesIn other words, Broadway pizazz is not the problem; often enough, it’s the solution. A set that can change locations instantaneously, or costumes that pin down time and class with almost taxonomic exactitude, can anchor while also heightening the illusion of life.That’s true even in nonmusical plays that have become much more visually abstract in recent years. You seldom see sofas and kitchen sinks onstage anymore, and even more seldom miss them. The 164 years of American commerce covered by “The Lehman Trilogy” take place convincingly in a rotating glass box.But for the most part, hyperdesign is a hint that something fundamental is missing. Often that missing element is the conceptual discipline that allows a piece of theater, even when set on an empty stage, to hang together and score its points. You can see it working perfectly in shows as wide ranging as David Byrne’s “American Utopia” (with its sleek aluminum chain curtains) and “Dear Evan Hansen” (with its hypnotic walls of online data) — productions in which design and direction go hand in hand.And you can see it, perhaps most vividly, in “Six,” which turns conceptual discipline into a fetish. Each of the wives of Henry VIII depicted in this sing-off gets her own theme color, song genre and pop star queenspiration. And though the set is minimal — it might have worked just as well for “Diana” — the lighting (by Tim Dieling) and costumes (by Gabriella Slade) are rock concert maximal, expressing the story’s ambition to thrill.Which it totally does, because sometimes the secret to effective design is proportion — and knowing when we really need the confetti. More