You have to switch to a 4 man defense and start by shipping out *at least* Bonucci, Isla and Giovinco to fund a new winger or two.
Ogbonna can back up Barzagli and Chiellini. Lichtsteiner and Caceres can handle RB just fine.
Right now I see our team like this for a 4-3-3:
Lichtsteiner-Barzagli-Chiellini-????
(Caceres)-(Ogbonna)-(Ogbonna)-(Peluso)
Vidal-????-Pogba
(Marchisio)(????)(Asamoah)
????-Llorente-Tevez
(Pepe)-(Vucinic)-(????)
Your top 2 priorities would be LB and RW. You could put Pogba into Pirlo's spot and put Asamoah/Marchisio at LCM but I think I'd rather shoot for the best team possible and that includes Pogba at LCM, not DM.
So you can fill DM maybe with Marchisio/Asamoah or you have to find a new player, maybe Radja. I don't want this player to be a slow regista like Alonso on a free. Let's move on from Pirlo please.
RW needs to be a great player. Bonucci + Isla should be at least 15M. Include 15M from our pockets and you can get a great player like maybe Di Maria. Take advantage of the Coentrao rumours as well please and the free DMs available.
Lichtsteiner-Barzagli-Chiellini-Coentrao
(Caceres)-(Ogbonna)-(Ogbonna)-(Peluso)
Vidal-Fernando/Matuidi-Pogba
(Marchisio)(Padoin troll)(Asamoah)
Di Maria-Llorente-Tevez
(Pepe)-(Vucinic)-(Cerci troll)
good team with a modest investment.