2974 - Chuck Foster is born on Earth.
2990 - 16-year-old Chuck accidentally drinks a ginko formula & gains his powers.
2993 - 19-year-old Chuck earns a job as the pilot of the Legion Cruiser.
2994 - 20-year-old Chuck saves the entire Legion of Super-Heroes from the White Triangle Daxamites and earns a full membership.
2996 - 22-year-old Chuck sacrifices himself during the Earthwar to save Luornu Durgo. She gives up one of her three lives to save him.
3001 - 27-year-old Chuck becomes a major on hero on Earth.
3005 - 31-year-old Chuck joins the reformed Legion of Super-Heroes, helping them access Earth as they battle the Dominators.
There is a fantastic legacy of heroes with really out-there powers in the Legion. This includes some characters that turned up in the semi-regular recruitment drives the classic Legion would host like the always hilarious Arm-Fall-Off Boy (if you hadn't heard of him before, you're welcome), to actual Legion members like the classic Matter-Eater Lad and of course, Chuck himself.
Bouncing Boy might have a pretty fun power, but where he really stood out was the fact that he was one of the very first overweight superheroes ever. This might not seem all that revolutionary; after all, he's still a white straight male character. But there were some real issues with depicting a character like Chuck that lasted through the Legion's entire run. In classic continuity he actually lost his powers all the time, retiring with Luornu and raising a family, although they continually came back. Subsequent versions of the Legion would often not include Chuck at all, and that's very likely just as much to do with his size (which... honestly, the kid's not THAT big) as with his left-of-normal powers.
Still, the kid was there, a classic member of one of the longest-running superhero teams in comics. What's more, he got the girl. That's pretty cool.
If you're going to have one of the Legion's classic weird-power characters on the team it really has to be Chuck, for a variety of reasons. Probably the biggest is the Legion of Super-Heroes animated series. They found a fantastic characterization for him, making him an eager character that WANTS to be on the team, and who earns his spot by way of a job as their pilot. that's a fun back-door that allows him to really step up and prove himself over time, which is always fun to see.
Second, of course, is his story with Luornu. They were always one of the most rock-solid romances on a team that basically introduced soap-opera storytelling to comics, and you want to see that play out.
Finally, as we're incorporating elements of the five-year storytelling gap from the classic Legion timeline, it's actually very cool that Chuck, one of the few Legion members actually from Earth, gets to spend those five years as a solo hero and becomes heralded as one of the greatest heroes on the planet. We all agree that it's a very cool thing to happen to a character that totally deserves it.