With a headliner like Kanye West and sponsor Cartier helping to underwrite the event, the Museum of Modern Art had no trouble drawing a big crowd for its annual Party in the Garden: Some 700 guests turned out for dinner, while the after-party attracted 1,500 patrons. But this year, as in years past, the institution's planning team sought to widen its base of supporters even further and find new ways to keep the spring fund-raiser fresh.