WAITING for the Sunday afternoon ferry from Seattle to Bainbridge Island, one driver proclaims via the California license plate on his snazzy little Japanese auto that he's a "BIZ WHIZ." A tourist, perhaps, en route to the Olympic peninsula. But given the lack of luggage and his general I've-done-this-before look, more likely a newcomer headed back home with the rest of the Seahawks fans.For most of the 200 and some-odd years since Capt. George Vancouver put in here, Bainbridge has been an independent and isolated neighbor of the big city just seven miles across the water. It has remained largely rural - a summer retreat for the wealthy. And that's been just fine with most people. Suzanne Downing, editor of the weekly newspaper here, is only half-joking when she says, "Here on the island we define the world as: (1) On Bainbridge Island and (2) Somewhere else." Recently, there's been an influx of newcomers attracted to this bucolic spot right next to the boomingest city in the Pacific Northwest. And it's not only changing the nature of the island, but causing a political and social split that's being seen in much of the West. As in a lot of places, it's the newly arrived who want to preserve the character of the island by limiting growth; those who've been here a long time want to be able to develop their land as they see fit. This tug-of-war, writes island author Andrew Ward, who moved here from Connecticut four years ago, "is probably as close to class warfare as you get out here." New houses and condominiums are going up at record rates, and the average price of a single-family home is approaching $250,000. State education officials predict that Bainbridge will gain another 850 school pupils in the next few years. Islander Brenda Bell wrote in the Sunday Seattle Times/Seattle Post Intelligencer magazine earlier this year th at the island "is having a middle-age identity crisis." Meanwhile, newly hired police officers and teachers can't afford to live here, a situation Janet West of Helpline House, a local charity group, finds "scandalous." Notwithstanding the relative wealth of most newcomers, several hundred island families have quietly sought help to pay grocery and heating bills. Changes in the community, reports city administrator Lynn Nordby, have resulted in "a tremendous amount of competition for space, for services, and for resources." Police Chief John Sutton says his biggest problems are "growth and traffic." Many islanders are concerned about the recent emergence in white supremicist activity here. On Veterans Day, city officials and the 1,200-member "Committee Against Malicious Harassment" held an all-day public forum called "Building a Healthy Community." Everything came to a head a year ago with a vote on whether Bainbridge should form an all-island government by incorporating as part of Winslow, the one small city here. The result split islanders right down the middle; out of 6,379 votes cast, the measure passed by just 140 votes - 2 percent. Opponents have gathered more than 2,000 signatures to put the issue back on the ballot, but they would need 60 percent to overturn the earlier vote. Meanwhile, Mr. Nordby and the other recently appointed administrators of the newly incorporated island government are scrambling to accommodate the inevitable change. One proposal has been to charge school "impact fees" of up to $7,000 for each new house built on the island. "There's a lot of controversy about what kind of environment we want to keep," says the Rev. Scott Huff, a Methodist minister who joined other community leaders in a forum sponsored recently by a local Christian Science church. "We've always been a place where people cared for each other, but with the influx of new people we see that kind of slipping away." But there is a sense that concerned citizens - whether they've been here for generations or just a few months - can preserve what has made Bainbridge Island a unique place. Says Walli Corn, who works with a drug education program: "Together it is possible to do for our community what we need to do."