Nah. C Ronaldo was "homesick" for a warmer climate i.e. Madrid. Cesc was "homesick" for Barca., Tevez, Navas, Balotelli etc. Hummels would be only German on the team. I've been over all this before...
This is without taking the "slowness" of Hummels as well as the price tag into account.
They were better career decisions not "home sickness"
Navas was the only one that genuinely had that problem (medical I heard)
I already said what I had to about "pace" and a top quality CB doesn't come cheap.