OK so I have been debating some ideas about lightsaber crystals and now is as good a time as any (see IC for why

). With the crystals found at the entrance to the Star Chamber, you can make whatever color lightsaber you want. The rules on how to craft your own are found under the Jedi Class…
Build Lightsaber: at 5th level and beyond, you can build your own lightsaber. To build a lightsaber you also need Force Sensitivity and Weapon Proficiency (lightsaber). You must spend 1,500 credits to obtain the basic components and 24 uninterrupted hours of constructing the weapon. At the end of the time, may a DC 15 Charisma (Use the Force) skill check. If you succeed you have completed the lightsaber construction, failure means you must wait at least 24 hours to start over. Once the lightsaber is constructed you can spend a Force Point to attune it to you and thereafter you gain a +1 bonus on attack rolls made by your personally made lightsaber. No one else who uses it gains this bonus. If you wish to build a double-bladed lightsaber it costs 3,000 cr.
Now with the special crystals that you found I like the idea that you have some additional options for your builds. You can choose one of the following additions to your lightsaber…
+2 damage with melee attacks with it
+2 to Charisma (Use the Force) skill rolls with 1 particular Skill use (like ‘Sense Surrounds’ or ‘Sense Force’) or one particular Force Power (Force Slam or Mind Trick)
+1 or +2 to certain Talents use. This will depend on the Talent, but board ones like Lightsaber Defense would add an additional +1 to all your Defenses when you have an ignited lightsaber in your hand. Or like Block or Deflect (if you take Deflect and then also Reflect it would count for this Talent also) would add +2 to your Reflect defense vs. the type of attack if you spend a Bonus action.
Maybe reflect a minor Feat like Danger Sense if you have the lightsaber draw and ignited (but this is case by case and I get to rule no depending on the feat).
Maybe an Expertise or just Proficiency with a skill (not Use the Force) when you have the lightsaber on your person (whether it is draw or ignited or not).
Some other minor affect I have not considered