Real Madrid has signed Isco, Casemiro and Carvajal. But it's true that the club should still add some more players to the roster. Higuaín will likely be gone soon and Xabi Alonso might not be ready to play 50 games anymore. That's why Real Madrid is looking to add a midfielder after the signing of Cavani is almost ruled out.
It will be hard to find Xabi Alonso a good replacement who accepts to be on the bench. Alonso is probably the ideal starter for Carlo Ancelotti in the defensive midfielder position, but he needs some rest as he's not able to play 50 games in a single season anymore. To sign Geoffrey Kondogbia would make a lot of sense. He's young and he has a lot of room to improve, and he could also learn from Xabi Alonso. Furthermore, it seems that he would be available for only 8.5M€. Kondogbia is far more defensive-minded than Alonso, but his presence on the pitch would not hurt Real Madrid with the likes of Modric, Isco and Özil creating plays for Benzema and Ronaldo. And he's only 20 years old.
Then there's Gündogan and Verratti. These two guys aren't better than Xabi Alonso now, but they will need to play more than Kondogbia in order to reach their potential. Gündogan and Verratti sould surely expect more minutes than Kondogbia, and both of them would be far more expensive. If Alonso is to be Ancelotti's starter this season, it will be better for Real Madrid to wait a year before trying to bring this kind of players to the roster.
And that's where Andrea Pirlo comes in. The Italian midfielder is older than Alonso, but he still has 20 quality games per season on his boots. He could give Alonso rest when needed. Problem is, he will be far more expensive than his true value considering his age. Juventus are going to try to contend in the Champions League next season and that's why Pirlo would not get out of Turin cheaply. Barcelona midfielder Thiago is not a pure replacement for Xabi Alonso, so Real Madrid's interest depends on what system Ancelotti wants to play with. Thiago would be available for 18M€, but if Barcelona refuses to negotiate Real Madrid would need to pay a considerable amount in taxes (around 10M€ more). That's just the way buyout clauses work when two Spanish teams are involved.
Nonetheless, maybe Zidane and Ancelotti trust Casemiro enough to take on that Alonso-replacement role that Real Madrid need. The Brazilian midfielder looks promising, but there are some concerns about his physical adaptation to the European tempo of play.
Real Madrid have almost ruled out the possibility of signing another striker. With Gonzalo Higuaín likely signing for Arsenal in the next few days, the roster would need a replacement for Karim Benzema. And that's Álvaro Morata. The young canterano has shocked the football world by winning the U21 Eurocup Golden Boot playing alongside new signing Isco. He might as well deserve Ancelotti's trust after all. To sign Cavani for more than 60M€ to have him or Benzema on the bench would make no sense. Karim Benzema will start the season as Real Madrid's main striker and then his own performances would be the ones that make him keep or lose that role.
Everything ends with Gareth Bale. Florentino Pérez obviously wants to bring the Welsh attacker, but Tottenham's President Daniel Levy asks too much. If Bale finally joins Real Madrid, Ángel Di María will be sold. The Argentinian winger will stay on the roster otherwise. If Di María is willing to join Tottenham, the London-based team would as well accept him in order to lower Bale's transfer fee.
Callejón will likely be gone as well to make room for Jesé. Jesé is performing quite brilliantly in FIFA's U20 World Cup, where he's the current leading scorer with 4 goals in 3 matches. His contract expires on 2014 but Zidane and Pérez trust him enough to sing him for the long term.