Your theory isn’t bad, but it’s also about the 100th time I’ve read the same thing.

There is one glaring flaw in your theory though. You said, “The lightsaber had been in Obi Wan’s possession for 20–30 years or so between episodes 3 and 4" (Symbolism of the lightsaber, para. 1). There is exactly 17 years between episode 3 and 4. Episode 3 shows Luke and Leia’s birth and they are 17 in SW:ANH. Okay, so that’s not glaring, but that is a pretty big oops. ;)

Honestly, there is one thing I don’t think you mentioned: Is Rey’s dad Ben’s son, or is her mom Ben’s daughter? I vote her mom is Ben’s daughter, which means she needs a dad. And I guess Luke is her dad. That’s right. Ben is a Kenobi-Skywalker hybrid. And that’s the biggest reason she is so strong in the force. Also, we’ve met her mom. Her mom is Captain Phasma, that cool looking, but underwhelming, Storm Trooper. She is a double agent within the First Order, using the force to keep her true identity hidden (like Palpatine did with the Jedi counsil), insuring that the first order never finds Rey, who was reining with Kylo under Luke years ago. It also explains why Phasma was so quick to lower the shields.

If this is true, my brain will explode with glee. :)

May the force be with you.

~adam