Experience
David Villa has won pretty much everything there is to win. At club level, he's won domestic leagues, domestic cups, European cups and the World Club Cup. At international level he has won a World Cup and a European Championship. As an individual, he has won a huge assortment of honours, such as the Euro 2008 Golden Boot, Spanish Player of the Year, inclusion in the UEFA team of the year and the honour of being the highest goalscorer in Spanish international history. Bringing this kind of winning mentality to Spurs is nothing to be sniffed at - even if it's only for a couple of seasons. Also, having Villa playing alongside a newly signed younger striker (such as Damiao, Benteke or Aubameyang) - and indeed the rest of the Spurs team - will undoubtedly rub off positively on them. You can only learn good things from a player of Villa's quality and experience.