84,000,000 BCE - Rip Hunter saves Karen the Velociraptor.
1855 - Rip is stranded for 7 months in Deadwood.
1945 - Rip helps the Freedom Fighters stop Vandal Savage from developing time travel technology during WW2
28 years ago - Rip confronts Alan Scott when he returns from Ragnarok, warning him to stay hidden until the rest of the Justice Society return, lest his presence disrupt the timeline.
3 years ago - Rip saves Vera Black from the Daemonites when she frees Bunny from Manchester Black's control and reveals it's location. He helps her locate Tomorrow Woman, assisting the formation of the Elite.
2471 - Rip places the temporal technology in the museum for Booster Gold to find, solving the paradox of his powers.
2992 - Rip is contacted by Querl Dox to consult on his hypertime proof so that they can save Clark Kent and repair the timeline.
16,450 - Rip defeats the Sun-Lords, stopping them from disassembling time.
Rip Hunter is a character that's been around for a very long time. He was originally an inventor that used his Time Sphere to adventure across history along with his friend, his girlfriend and his girlfriend's kid brother. It's a pretty well-trod formula to have a surrogate family of characters going on fantastic adventures together; you probably immediately recognize it as a rough sketch of the fantastic four, but there are other comics like the Challengers of the Unknown that did it even earlier. Of course, you could also argue that Jules Verne was telling stories with the formula long before comics ever existed.
For quite a few years, Rip wasn't really able to see much action thanks to the intractably dense nature of DC's multiverse. He spent years as one of the Linear Men, a group of characters that existed at the end of time monitoring time, leeping exactly the sort of stories Rip used to star in from happening.
Of course, time travel adventures still HAPPENED. The Linear Men were essentially narrative dead weight. you didn't really see Rip again in a role of any significance until he became a mentor to Booster Gold in the 52 series, and then in Booster's new time-travel centric series. It was here that they leaned into the idea that Booster was a paradox, and that Rip was part of what solved that Paradox. It also tried to make Rip into Booster's son.
Modern audiences are much more likely to recognize Rip as depicted by Arthur Darville on the CW series Legends of Tomorrow. It's not a bad depiction, honestly, with his trench-coat and piloting his time-ship the Waverider (actually named after one of the members of the Linear Men). We happen to be pretty big fans of the classic sci-fi adventurer look; goggles, short jacket, sidearm... maybe even his sword. Also, while the Waverider as depicted on the series is pretty cool, there is one fact about Rip's classic Time Sphere that makes it a far more appropriate vehicle. It's the same fact that makes the casting of Arthur Darville such a clever wink at the audience.
Rip Hunter is absolutely DC's Doctor Who.
If we are going to make a timeline where Time Travel almost NEVER happens, having a character that is the exception to that rule is an absolute necessity.
We need someone to be able to move around the timeline freely, The ONLY character who understands exactly what it means to stay locked within the one ACTUAL timeline without losing his place forever. He can be the reason Alan Scott stays in hiding after he returns to the timeline. The reason Booster Gold is able to travel back from his home time. This makes Rip timeless, and the more we lean into that Doctor Who allegory, the better. To that end, we absolutely think that the time sphere needs to be a spatial anomaly... a small vehicle with a massive interior of floors upon floors. We shouldn't know where he came from or how he gained his knowledge. If we have to decide, he could simply be the lone person in history to develop the technology (or perhaps to have perfected the hypertime tech developed by Querl Dox, the only other character to have successfully cracked time travel). From there, he becomes a fantastic narrative tool, and a reason for us to pepper interesting time adventures across the timeline, from the distant future when he defends the universe and all creation from being unmade, to the late Cretaceous where he rescues his sidekick, Karen the Velociraptor.
Oh Yea. We gave him a dinosaur sidekick. He's a time traveler. He needs a dinosaur.