He made his competitive debut as City retained the Community Shield with a penalty shoot-out triumph over Liverpool at Wembley on Saturday, turning in an assured display.
Guardiola has been searching for a long-term heir to Fernandinho to operate at the base of his midfield for some time, with interest in Fred, Jorginho and Frenkie de Jong ultimately failing to bear fruit.
But De Bruyne feels Rodri has acclimatized impressively to a pivotal position within City's tactical setup and, at 23, aligns with the broader long-term plan of the club's transfer policy.
"He's a perfect fit for us. I think the way that we did transfers the last years add up," he said, with Guardiola's men now preparing for the start of their Premier League title defence at West Ham on Saturday.
"You see a lot of young talent coming in willing to play our style. I think that's what they're looking for and he's a perfect fit for us."
At Wembley, Rodri attempted more passes than any of his City team-mates, with 62 at a 91.9 per cent completion rate, and was level with defensive duo Nicolas Otamendi and Oleksandr Zinchenko for the most touches (74).
At almost 6ft 3ins, the former Villarreal man is an obvious asset to a largely diminutive side Guardiola famously claimed has to "go to the church to pray" when they concede a set piece.
He won all of his aerial duels against Liverpool and gained possession nine times – again the highest figure in that metric.
"I think he's the perfect DM [defensive midfielder] for the way we want to play," De Bruyne continued.
"Our DM is a really difficult position. You need certain players for it and there's not a lot of people who can do both sides of it.
"Obviously we're very good on the ball. You can't just be defensive, you have to be offensive also."
Working well in tandem with Rodri, De Bruyne turned in an all-action display as City were the better side in the first-half, taking a 12th-minute lead through Raheem Sterling.
It was enough for the Belgium international to be named man of the match and, although he credited Rodri's influence, he also cited operating somewhere close to full fitness being a factor, after two medial knee ligament injuries limited his impact during his club's treble-winning season.
"It wouldn't be different with Fernandinho there," he added. "It's maybe a difference with last year because I'm feeling physically better than I did last year. I needed more time.
"I think the way he's performed in pre-season and in training has been phenomenal. To be the new guy and still be on this level is a good sign."