Can we come up with some new runes?

As an older player (been playing since season 1), I wonder what other types of runes we could come up with.

For** example**: "Would it be possible to balance on-hit magic damage runes?" -or- "How could we make a health per hit rune work without breaking the game?"

I have been playing a little bit of HoTS and I like they way their block passive works. Maybe we could make a quintessence that grants a % damage reduction charge every so often.

I dunno, I just think there is some room to grow with new unique rune options to play with.
Just spit-balling as an old player here. What do you guys think?