I don't believe there are not better options than Camoranesi and Grosso (both barely even played) in the whole league. Hell even we have better players at Camo position in Juve.
So who are the better right wingers?
I can think of Camoranesi, Candreva and Maggio as the best 3 right wingers (although, Candreva isn't really a winger). All three are called in the provisional ~30 men squad and one of them won't be called probably. In the end, Lippi called the best 3 RWs and he'll pick two.
As for fullbacks, Lippi called Zambrotta, Criscito, Grosso and Cassani. Santon will probably be added later.
That's 5 players and 4 spots (2 LBs and 2 RBs). One of them will be excluded. All 5 can play at LB but Zambrotta, Cassani and Santon can also play RB. So two of them will surely be called as RBs, while one of them, Criscito and Grosso will fight for the 2 spots for LB.
Apart from maybe Balzaretti, I don't think you can add more fullbacks to this provisional squad.
As for Iaquinta, there are already a few players in the squad who can do Iaquinta's job much better than he can but in Ale's position, whether right or wrong, Lippi wasn't going to call neither Cassano nor Miccoli so calling up Ale still would make much more sense than picking up Iaquinta.
Are there better target men than Iaquinta in Italy? Yes
Are there better support strikers? Yes
Are there better strikers for the right side of a 4-3-3? Probably
Is there someone better than Iaquinta in all these 3 positions? No
Del Piero can only play in a two men attack, as a support striker, but even here Di Natale is (right now) much better than him. If Lippi's main and only formation was 4-4-2 or 4-3-1-2 then yes, Del Piero could have been called as a sub support striker.
But Lippi plays many different formations, and 4-3-3 is one of them and an important one. He will need at least 8 attackers to cover all these formations. He will need 2 target, 2 support strikers, 3-4 attackers who can play on the sides of 4-3-3 attack. There is no space in the squad for 7-8 attackers. With Iaquinta he uses one man instead of taking 3 players (3 sub players, may I add).