Spain are their own worst enemy. I really don't know what they're thinking not playing anyone upfront. I personally would play both a striker and someone else like Pedro or Mata, players who would stretch the defense by using the width of the pitch, making runs behind the opposition defense, and playing on the opposition defense's shoulders. These kind of players would complement the sort of football Spain's midfield likes to play, their is no use keeping possession of the ball, if you don't have anyone willing to move off the ball in the final third.
Also, i think Spain being an offensive team is a huge myth, i don't think they're an offensive team at all, i think they're a team that plays possession football, that prefers playing safe short passes instead of trying to take risks. Del Bosque focuses more on keeping the ball than actually carving out chances. They're content with winning games by one or two goal margin, and then just keep the ball for the rest of the game without committing too much to attack.
