Indoor track had never looked more fetching. At last week's two-day AAU meet in New York fans were treated to the spectacle of lithe young women leaping, running and soaring in a colorful selection of Capri stretch pants, turtleneck blouses, Bermuda shorts, leotards and bikini-short shorts. But if the variety of blossoming fashions was impressive, the exuberant athletes wearing them were more so. They came from Europe and Asia and all over the U.S., and when they performed they were almost as good as the men, and even more exciting. Indeed, the problem for some fans accompanied by wives was not to appear too enthusiastic when Mary Rand, the world's best woman broad jumper, flew into the air. Mrs. Rand has a nose that is too long, a mouth that is too wide and a haircut that is too short, but somehow they fit niftily with a smooth, pink complexion, a dazzling 36-24-36 figure and a buoyant, irresistible charm. She, Miss Chi Cheng from Taiwan and 208 others, many of them as comely, broke five records and provided some of the outstanding moments in a meet, reported on page 45, that in other ways was not always a success.