Warning! Spoilers ahead for Superman: Son of Kal-El #9
While Jon Kent's Superman may be struggling to fill his dad's shoes, he's just learned he's not the only hero who's ever felt this way thanks to Nightwing and his own similar experience. During their current team-up, Dick Grayson has become Jon's official superhero mentor, and there's no one better the new Man of Steel could have instead. While they have a lot in common, the biggest thing is their shared feelings about becoming their fathers given the season of time Nightwing spent as Batman's replacement.
When Bruce Wayne was believed to have been killed by Darkseid during Final Crisis, Dick Grayson eventually took over as the new Batman with Bruce's son Damian becoming Robin. As a result, the two of them were DC's new Dynamic Duo for about two years before Bruce Wayne returned, allowing Dick to eventually resume his role as Nightwing with DC's New 52 reboot. Now, recent comics have seen Jon Kent in a similar position where he's taken over his father's role with Clark Kent having left Earth indefinitely.
In Superman: Son of Kal-El #9 from Tom Taylor and Bruno Redondo, Superman and Nightwing have teamed up to investigate The Rising, a growing army of controllable metahumans under the command of corrupt Gamorran President Henry Bendix. In the face of this threat, Jon has also been struggling on a personal level, feeling as though he can't measure up or adequately live up to the role his father left for him. However, this is exactly what makes Nightwing such a perfect mentor for Jon with the reveal that his own experience as Batman was the same, feeling as though he hadn't earned or belonged in the role of the Dark Knight. As such, Dick gives the new Man of Steel some great advice for how to positively reconcile those feelings.
Rather than focusing so much on trying to perfectly emulate the original Superman, Dick's recommendation is for Jon to be his own hero. It truly seems like the best course of action, and it's certainly something Grayson has taken to heart himself even after he went back to being Nightwing. Being just like Batman (or in Jon's case Superman) isn't the way to go. Having his own style and methods as a hero is far better. That uniqueness is a huge reason why Nightwing has become just as popular as the Dark Knight himself.
Jon Kent's Superman has already displayed some new methods like being more proactive in world affairs than Clark was, and Nightwing's advice will hopefully encourage him further. It's better for Jon to walk his own path rather than worrying so much about being exactly the same kind of superhero his dad was. While there's still more of Nightwing and the new Superman's current team-up to come, it's clear that the newest iteration of the World's Finest needs to have many more partnerships beyond this now. They could even star in their own series together just like the original Batman and Man of Steel have had from DC Comics.