Balza's strong point is going forward and do some decent crosses, not that he is ultra secure as a defender, because this is what is valued today for a fullback, the ability to run fast forward and offer to the creativity of the teams play, also being fast allows him to cope with fast forwards and stop them, this is exactly what Chiellini is also good for,Chie isnt any better defensive wise either, but he is probably stronger, last year prooved that Balza is more accurate to his taclins over Chie and has a smaller tendecy to make sloppy fouls.
This season Balza is used as Chiellini's sub and maybe those few bad games is how its reflected on the field...
As for Treze, we souldnt rate him by the same standards a finisher, a creative mid and an all around forward like DP,
Neddy and DP have more wider abilities in the field, its a normal thing they can create more efficiently, Treze's role is to finish and he can do that better than anyone, he didnt miss many chances and fulfill his duty much worse than the rest,(dont forget that he scored a goal that was dissalowed) he also tried to do more than his role requires and did a few good "creative" passes, apart from that, his was cought offside many more times than an attacker with his exp sould...