The Problem with Runes

There is too much damage in the game, so you add a rune that when you shield yourself gives you more damage based off of the strengths of the shield and your HP? Why? Why the hell should anyone get more damage by building a stronger shield? Is this some kind of self sabotage? Does Riot just hate their balance team department and give them these impossible scenario?

The change to Clarity was going int eh right direction, but do that to all of your runes that give damage for arbitrary things. Like the one that gives you more damage based on CDR, or the one that gives you more damage based on if you dashed. We have comet, why do we need Airy to also give your abilities extra damage?

Why is scorch even a rune? it is so underwhelming it feels like a placeholder when you ran out of ideas. it is in the same row as Gathering storm and Waterwalking. Also on Waterwalking, why does it also give you more damage? Isn't extra movement speed for that mid lane roam more then enough?

Demolish is a stupid rune, why give full tanks tower pushing? What sense does that make at all. Your job as a tank is to help protect your team. you sacrifice damage so you can be the wall your team hides behind. And the same with Aftershock. A tank doesn't need extra burst that scales with his HP. It would be more then enough if it applies a slow on top of the bonus defenses.

With all these runes it is easy to stack most of them together to make a really powerful combo. I can be looking at an extra item and a half of AD or AP stats. How does one balance this i ask? You have to keep in mind that all champs can build these anyway they can, they can all have an extra 15-50+ AD or AP. Or not, they could build sub-optimal runes.