Danny.t, you must sign Vargas, He become World Class Winger for my team, Man Utd. Like johnk03m said, you need to train him as LB. Look at the screen shots. Vagnor Love is amazing in my games. He scores 25+ goals for Real Madrid in La Liga for each season.
For the midfielder, sign Veloso, Moutinho or Hamsik. The AMC, try sign Alan Dzagoev or Matias Fernandez.