The Nova Project.

[Kaden]

First of all, my singing is awesome.

For quints, I'd suggest picking up Armor Pen, and MR Pen in addition to what you already have.

Other random things:

Galio's played more as an AP carry/tank right now. He can be used as support, it's just not as common.

Run pretty much anything other than AS runes on Jax. He gets plenty of that stat for free.

If a bruiser and AD are equally fed, and the bruiser has a gap closer, the bruiser will win that fight most of the time. Yi is a particularly good example of this, since you can't kite him. If you had been, say, Udyr or Jarvan against the Ez, it would have been completely different.

Sustainability is a pretty big deal, and it's definitely not a bad thing to prioritize. Conventional LoL wisdom holds "win your lane, win the game" and if you can spend more time in your lane than your opponent, you're probably going to win it. Just know when you actually need it and when you don't. If everyone's running around teaming fighting, that vamp scepter probably won't help as much as a null-magic mantle or cloth armor would.

If you want to work on using skill shots well when things get a little crazy, someone like Caitlyn is pretty good for that. The skill shot isn't absolutely crucial to her performance (as opposed to champs like Galio or Cho or Ez) and is easy enough to use that you can get some good practice with it.