CHANGES ARE MOSTLY FOR THE BEST : RESTAURANT ADDS NEW ZEST TO DINING

MacArthur Park really is a delightful place: spacious and relaxed, full of natural light and cool sea air. The menu is more or less spacious and relaxed itself.

I can’t think of anyplace else in Orange County where you can choose between potato skins and grilled quail salad, beef chili and rabbit with rosemary butter, or liver with bacon and lobster sausage in green tomato sauce.

In short, it’s not a place you go to be ultraserious about food, but you don’t have to fall asleep in a bowl of split pea soup there either. MacArthur Park is, well, fun.

OK, it must be pretty obvious. To me, writing a column about MacArthur Park is sort of like having a week’s vacation. My official excuse is the fact that the restaurant changes its menu every so often; but in honesty, I have to say that the more MacArthur Park changes, the more it leaves a good thing well enough alone.

The changes involve maybe five new dishes in the latest menu, and the nightly specials often are old dishes that were benched to make room for new ones. By far the biggest change I’ve seen in 2 1/2 years is the fact that the old gourmet store is now a takeout section for the chili and ribs end of the menu.

Even the biggest problem about the place stays the same. Every time I’ve been to MacArthur Park, I’ve stood around like a fool for what seemed an hour waiting for somebody to seat me. I don’t know what the hostesses do when they’re not attending their station, but it sure takes a lot of their time.

But let’s talk about the new stuff. The baby green salad is a light and whimsical one with jicama strips and toasted pine nuts. Quite a fascinating new side order is the cold, julienned sweet potatoes in a sweet-tart tequila and lime dressing. The tasso sandwich is pretty new, to me anyway--a stirring concoction of peppery, smoked, thin-sliced pork loin on an onion roll with the usual sweet barbecue sauce and a lot of grilled mild green peppers, a heap of skinny french fries on the side.

There’s a new veal chop--a cautious but respectable one with roasted shallots and wild mushrooms. Finally, the lobster sausage, which differs from the usual local model in being more like a frankfurter than a rough country sausage, is very tasty in its tart green tomato sauce, with unusually good toast points--they’re toasted slices of brioche.

Among the standbys that haven’t changed, the sourdough has always been good at MacArthur Park. The ordinary fun foods are still unusually good too. Crisp, paper-thin onion strings without a speck of oil. “Nanny’s Chili” is a surprisingly Mexican version of chili con carne, with the smoky, chocolate aroma of pasilla peppers.

This place made its name as a grill, and grilled fish (and there are still three fish specials a day) and barbecued meat remain the backbone of its menu. The ribs are the baby back sort, which rib eaters may not consider quite serious, but they are deliciously smoky. Likewise, the exemplary barbecued chicken (the barbecue sauce is perfectly acceptable to the faint of heart).

The cold, grilled tuna sounds like a terrible idea--partly grilled tuna, charcoal burnt on the outside, but mostly quite raw, in a tangerine-mustard sauce with fresh fennel scattered here and there. In fact, it’s great. It has the textural interest of good sushi with the added thrill of mesquite, and the sauce is more mannerly than its giddy name suggests. (By contrast, the smoked raw beef, which sounds like the meat-eater’s version of the same idea, is a fairly conventional carpaccio. )

Still, despite a lot of intriguing adventures, I think the things MacArthur Park does best are relatively conventional. The best entree in the house is probably the dry-aged New York steak with onion rings, unless it’s the milky-sweet fried catfish.

Some of the more adventuresome dishes leave me cold. I find the herbed goat cheese on cold shrimp and scallops with eggplant to be positively impolite about its goaty origins. As for the grilled pasilla peppers filled with three cheeses, I’m sorry, but I don’t believe God meant for Roquefort to be served above room temperature.

Apart from the somewhat Italian idea of pear poached in zinfandel, desserts are rather American. The vanilla ice cream is outstanding, especially with hot caramel sauce. Strawberries are served on real shortcake with real whipped cream. In the chocolate addiction department, there’s a mud pie with lots of walnut chunks in the chocolate sauce and a homely looking “turtle pie,” which, I expect, is meant to emulate a certain candy (the filling is essentially a layer of chocolate candy).

One of the astonishing things about MacArthur Park is that the servings are substantially larger than you expect at any place that 1) serves quail salad, or 2) overlooks a body of water (in this case the marina at Sunset Beach). Another is the prices, which are not at all bad. Appetizers are $2.95 to $5.50, salads $2.95 to $7.65, and entrees $7.35 to $15.95. Desserts run $2.75 to $3.90.

MACARTHUR PARK 16390 Pacific Coast Highway,

Huntington Beach

(714) 846-5553 or (213) 592-5578

Open for lunch and dinner daily. American Express, Diner’s Club, MasterCard and Visa accepted.