Ngoma made his first appearance of the season as a 67th minute replacement for Lyle Lakay in 2-2 draw with Golden Arrows at Princess Magogo Stadium on Saturday.
The former Orlando Pirates winger was previously sidelined with a knee injury sustained on Bafana Bafana duty at the COSAFA Cup in June.
"It was just so lovely to have Aubrey back in the team from his injury and he was able to get through the game without any knocks," said McCarthy.
"For me that was just the biggest positive of the game, to have Aubrey back and the impact he had on the team when he came in. Because everyone could've dropped their heads, 2-0 down, playing the team that was second on the log and playing very well. Overall I'm happy."
McCarthy plans to start Ngoma, who scored seven goals and made 16 assists last term, in their next match against Maritzburg United in Cape Town on December 5.
"Next game I'll be looking to throw him in straight away because he brings intelligence to the team and obviously his presence is very vital because he was super important for the team last season.
"This season it was unfortunate that he got injured. So now he's back we are just looking to bring up his confidence in training. He looks like he's flying and he should be playing with what you see in training... but training and matches are completely different.
"But having him, it'll be like having a new player out there."
The Citizens are fourth on the Premiership table with 17 points from 11 matches - two points behind leaders Baroka.