1) Id use passion4fms possession/barcelona/tiki taka tactics AND/OR bayern the art of counter attack by cookiemaker (search for them). Or make a tactic yourself using wide players *(wingers/IFs) as you ve got good players there.
ST: Either Aspas (8.75m rel clause)/Sassa 4.4m rel clause.
CAM: If you buy both the above they can be utilised there. Otherwise look at matheus who has a 1.9rel clause and is awesome.
CB: Any of Strandberg (1st choice)/Sviatchenko/Almeback/Alex Milosevic are cheap and would be great (more expensive: G Burdisso/Bellusci/Andia)
GK: Pierrick Cros/Costil (latter is expensive). Or wait till summer and get in Ospina. Marchetti (Lazio) is great but expensive.