I've come back from a about a 6 month hiatus. What have I missed?

Some of you might be wondering "Why come back at all?" Well, I'm coming back for one reason, and one reason alone: I plan to try and get a job at Riot as a Software engineer sometime in the future. However, in order to do that, I need to learn how to play this game, and play it WELL. Yeah, I know, I may never get that job, but it doesn't hurt to try.

Now, mind you I have kept somewhat up to date with whats been going on, but I may as well get a community overview. I believe I left when Hextech Crafting was still partly experimental on the PBE, and it was a few weeks before Aurelion Sol was teased (not revealed, TEASED) Jhin was still relatively new to the scene, and the mage update was nearing completion, but was not released (I think, correct me if I'm wrong). All of this just to give you guys a good idea of when I left.

Why did I leave? Well....lets just say I had an incident. I won't go in to any further details.

I am aware that mages and mage items got a major overhaul, Aureilon Sol (obviously) and Taliyah have been released, Ryze got reworked (again) along with Taric, Hextech Crafting is thing (maybe?), and Assassins are up next for group rework. And thus, with all of that, what can you guys tell me that I may not know?

P.S. If a Rioter happens to stumble upon this post, would mind at all revealing what kind of degree you have, if any at all? I'd just like to get an idea of what I should be aiming for.