I really think we need to invest heavily in our attack. Borriello, Quags, and Matri are just not going to cut it. That strike force is befitting of a team like Cagliari, or Genoa, not Juventus FFS. We desperately need a RWF as well. The CL is a whole different ball game, and if we don't wish to humiliate/embarrass ourselves, we need to invest heavily. Our midfield, and to a lesser extent our defense, are competitive, and with a few minor adjustments will be good to go.
Players like Pepe, Giac, Matri, Quag, and Borriello seem out of their depth when it comes to the CL (remember, we had no European commitments this season, and Serie A as a whole has seen a drastic reduction in the level of quality, both in terms of personnel and level of play); the only player in our attack who seems competent on the European stage is Vucinic. Hence, we need a quality RWF, and a top notch striker to compete continentally, and be able to deploy both formations (4-3-3, and 3-5-2) efficiently and effectively.
Ideally, I'd bring back Gio, acquire Ramirez, and Cavani/Higuain. If we get Dzeko or Damiao, I think a higher quality RWF is essential; someone like Suarez comes to mind. However, if Gio must be sacrificed for funds, then so be it. It seems that Verrati and Pogba are ours, so I don't really see the need for Nainggolan. In any case, I'd prefer Asamoah over him. For the defence, Ogbonha is the superior defender, but it seems Astori is the more realistic option. We should avoid Bochetti; I don't really rate him at all. DC, and Chiellini filling in at LB if need be, seems sufficient for now.
Add Destro for depth, youth, and quality in attack, and we are set.
Regarding sales, we should dispose of Elia, Krasic, Pazienza, Padoin (if we get a good enough offer), Esti, Melo, Ziegler, one of Matri and Quag, and send Borriello back. I know Del Piero seems on his way out, but I firmly believe his experience will prove invaluable, particularly in Europe. Giggs and Scholes are still playing; I don't see why Del Piero can't continue at the highest levels for another year or two, especially in a limited role/capacity.