Lancaster's side are trying to establish a more attacking style and the Durban-born 26-year-old conceded that there was still room for improvement ahead of Australia’s visit to Twickenham this Saturday.
“We were really pleased with the intent we showed,” Barritt told the RFU website.
“The team showed a willingness to play from all corners of the park but we definitely need to work on our execution.
"We left a number of tries out there and the team will just look to improve this week ahead of Australia.”
Barritt continued: “It was a very pleasing start though and we executed a lot of what we wanted to do. Subtle lines and work off the ball was pleasing but we know there is plenty more to come and know our execution can definitely get better.”
The Saracen’s centre was making his eighth England appearance last weekend against the southern hemisphere side and believes that his personal performances are improving game-by-game.
“I was really pleased with how it went," he said.
"I showed different aspects to the game with carrying, distributing and running lines off the ball which is what we have been working really hard on – but there is always room for improvement.”