Some years ago, Criterion released a box set of films from BBS Productions. BBS stood for Bob Rafelson, Bert Schneider, and Stephen Blauner. They were part of the emerging "New Hollywood". The films included in the box set give a sense of what BBS was about: Head, Easy Rider, Five Easy Pieces, Drive He Said, The Last Picture Show, A Safe Place, and The King of Marvin Gardens.
I saw The King of Marvin Gardens when it came out, and didn't think it was the equal of Five Easy Pieces, also directed by Rafelson and starring Nicholson. It seemed that Nicholson was miscast as an introvert who hosts a radio show where he tells stories. Bruce Dern played the "Nicholson" part, the extrovert with dreams. Looking back, I'd say that Dern was always capable of a variety of roles, and he isn't out of place here. And Nicholson has gotten some praise for his performance here, although I remain mostly unimpressed. For one thing, the long monologues that his character gives are boring and obscure. It's hard to believe any radio station would play his show. Also, I think he gets praised too much for not being "Jack Nicholson".
Ellen Burstyn gives everything she has to her part as an aging prostitute, but as Kael noted, "Ellen Burstyn works valiantly, but her role is a series of florid gestures", which isn't the fault of the actress. Julia Anne Robinson rounds out the main cast ... she was just getting started in her career, and she sadly died soon after the film was made in a fire. Scatman Crothers livens things up when he appears. And director of photography László Kovács does his usual job of making a movie look great, whether the movie is good or not.
I wrote of A Safe Place, "It does make me nostalgic for that period of American movies, and its experimental nature is worth praising. But I could barely stay awake when I had to actually watch it." Much the same can be said for The King of Marvin Gardens, although I had no trouble staying awake, and thought it was OK where I really disliked A Safe Place.