I think this is only one dimension. Player height, weight, left-footedness or right-footedness might also be crucial in figuring out how to beat Spain. At the very least, you know that Xavi is a key player in the entire network - of course, from mere observation, many have that assumption already but from the graph, you'd know who are the top 3 passers to stop.
I'd also take into account the positioning of the players on the fields, the runs that they make and etc. It'd be interesting if someone can build a simple simulation of how Spain's positional play (measuring distances between the players) based on tracking the last few years of the Del Bosque's management.
You wouldn't miss Xavi, but I'd say it would be a lot easier to miss Busquets. His style of play doesn't get as much attention, because he does very little, but what little he does has the biggest impact: http://www.youtube.com/watch?v=ijDdpNxPyPU
I'd also take into account the positioning of the players on the fields, the runs that they make and etc. It'd be interesting if someone can build a simple simulation of how Spain's positional play (measuring distances between the players) based on tracking the last few years of the Del Bosque's management.