LOS ANGELES - Toyota's first-generation Sequoia was dinged for being smaller than other large SUVs. Now some Toyota executives fear that a much bigger Sequoia, which arrives next fall, swung too far the other way. Sales of big SUVs are shrinking, and for more reasons than expensive gasoline. The bigger-is-better fad has passed, executives say. And the bigger Sequoia may arrive just as the party lets out. "I worry about the Sequoia being too big and not having enough fuel economy, more than I do with the (redesigned) Tundra," said Don Esmond, senior vice president of automotive operations at Toyota Motor Sales U.S.A. Inc.