This is only set a couple of years before Rogue One. Actually close to four years. So he would be younger, but not quite that young. :)
@Burning Kitty I think both of them have potential. What I would say, is make sure that they don't become caricatures. What I mean by that is, the Jedi with Mandalorian armor. I love the idea, just make sure that it can fit into a story. There is a lot that can be told by a Jedi in Mandalorian armor, trust me, especially if she meets any Mandos, other that Boba Fett (who isn't a Mando).There are two things she hates in the universe Mandos & Sith. Sith is a very distant second. It's majorly repainted to the point of no one would look at it and think the person wearing was a Mando, think something that a Mando would super insulting. Plus it isn't your modern Mando armor like your character has. Think Knights of the Old Republic not that horrible MMO the one with Revan and the Jedi Exile.
I also don't have an issue with the other character, just make sure to remember that kyber crystals are sentient in their own right. Sith crystals aren't red because they found red crystals somewhere. Sith/Dark side crystals are red because kyber is naturally in tune with the light side of the force. So, when a darksider uses a blue/green/etc lightsaber to kill out of anger, or fear, or any other dark emotion, the crystal begins to bleed. When the crystal bleeds, the saber blade takes on a red hue. So, your character would need to have done some nasty stuff, and it would need to be said for sure to flesh her out.She is not using a Red Kyber she is using her Jedi Master's Kyber crystal. She destroyed the Red one. Only way she would reveal what she did is if she thought someone of importance to her was about to find out. Random rebel red shirts she couldn't give two shits if they found out, they be dead soon enough anyway.
Guess I should have thought this through more. I didn't realize how many people hated the new canon, and the worlds of Star Wars are extremely hard to bring together without having too many rules. We can continue, or we can brainstorm ideas for a plot before we start the RP. Honestly, I'm a little disheartened.