Goals from Miguel Angel Britos and Gonzalo Higuain helped Napoli to a 2-1 victory at Milan, putting them second in the league to Roma on goal difference.
Mario Balotelli had a penalty saved by Pepe Reina on the hour-mark before scoring a late consolation goal and then being sent off after the final whistle for dissent.
Benitez was happy with the victory but believes his team still have plenty of room for improvement.
"We worked together as a team tonight and that was very important, as if you have that then the quality players get the chance to shine," he told Sky Sport Italia.
"I like the way my team are playing. I'll say we are now at 73 percent, but we can still improve these little things and when we do it'll be easier to win."
Reina's save from Balotelli saw him become the first goalkeeper to save a penalty from the 23-year-old striker in a competitive match.
The on-loan goalkeeper was glad his homework paid off as he dived to his right to keep out Balotelli's average spot-kick.
"As always, we studied the Milan players. We knew Mario was very strong at penalties, but I managed to get it," Reina said.
While he insisted his side have work to do, Benitez said claiming three points at the San Siro was enough to please him.
"Milan played well, so it wasn't easy for us to counter Balotelli's position between the lines," Benitez said.
"We needed to make adjustments and are at the start of this journey, so we need to improve many things, but winning away to Milan a coach has to be happy.
"The important thing was to show this character right to the end. It wasn't our best performance of the season, but to come here and win for a fifth consecutive victory (in all competitions) is impressive."
