Noel Holston TELEVISION Landon's 'Heaven' is down to Earth Separate screen credits tell us that tonight's two-hour premiere of Highway to Heaven is a Michael Landon Production that was written by Michael Landon, directed by Michael Landon and stars Michael Landon. Does this guy's ego have any bounds? Probably not. The Highway to Heaven character he devised for himself is an angel who wanders around the U.S. A. trying to get people to be nicer to each other. The messianic complex Landon displays is so strong that some of NBC's own programmers refer to the show as "Jesus of Malibu." Landon is not well-loved among TV critics, and the feeling is mutual, mostly because of what critics said about his last series, Lit-tie House on the Prairie. Not that anybody trashed that wholesome, well-meaning show, just that very few gushed over it. And Landon took it personally, as if his vanity had been insulted, when critics wondered why pioneer patriarch Charles Ingalls wore what looked like designer overalls and $75 Ju-lian-of-Beverly-Hills haircuts. All this is brought up for a purpose, to make it clear how many biases I had to put aside in order to make the following statement: I sort of like Highway to Heaven. Imagine how people who have no trouble tolerating Landon, or who actively like him, are probably going to feel about the show. Landon, as mentioned, plays an angel who goes by the name of Jonathan Smith. Jonathan wears combat boots, fatigue pants, a faded Army-green undershirt that shows off his biceps and anach-ronistically long hair. The suggestion, though it's never confirmed, is that Jonathan was dispatched to heaven while in Vietnam. In tonight's show (8-10), he takes a job as a handyman at a dreary, suffocating nursing home and proceeds to rekindle the patients' interest in life. Almost overnight, he has them outside planting flowers and grilling hamburgers, and the nursing-home manager chewing him out and worrying that someone's going to get hurt and file a lawsuit. Jonathan also gets involved platonically as far as he's concerned with a mousy young woman named Leslie Gordon (Mary McCusker), who works at the home, and her brother Mark, an embittered ex-cop. By episode's end, Mark, who's nicely played by Landon's bearish friend and Little House co-star Victor French, has uncovered Jonathan's secret, helped him to save the home from a developer who would evict all its residents and decided to accompany the angel on his good-will mission. Highway to Heaven is so statically directed by Landon that some scenes have all the natural alacrity of an animatronic display at Disney World, and he is hardly a master of writing unaffected dialogue. What saves tonight's show from its technical shortcomings, and keeps it from dissolving into silliness, are the essential decency of the premise and the understatement with which the "miracles" are performed. Like any human, Landon errs sometimes, but that doesn't mean he isn't a pretty smart guy. Between Bonanza and Ltttie House, he's enjoyed unbroken success on TV for 25 years, and I don't think Highway to Heaven is going to spoil his streak.