[Mark]

If it were for me, I'd choose a world class defensive midfielder, from the likes of Essien, Cambiasso, Mascherano or even De Rossi.
The second target would be Sergio Ramos as you said, he is a monster sometimes (but he is virtually impossible to transfer).
Finally, I'd choose a forward that could push defences towards their goal. Eto'o is magnific, but I'd like something like Ibrahimovic or Drogba too. My personal favorite? Luca Toni!