The defending Premier League champions are now unbeaten in 17 games stretching back to last season and sit top of the table.
City have lacked some of their swagger from their title-winning previous campaign but they are showing signs of getting back to their best.
"In the first half we scored only one goal but we had other chances to score," Mancini told Sky Sports.
"I think that we had a good attitude today."
Two goals apiece from Sergio Aguero and Carlos Tevez, including both Argentines scoring a penalty, after David Silva's opener dumped Villa into the relegation zone.
Villa were annoyed at the decision of the match officials to award Aguero's spot-kick for an apparent handball by Andreas Weimann.
But Mancini said: "From the bench it is difficult to say, because we did not see anything."