I think it would be nice if there was an explanation and preview for runes on the rune infusing screen (see attached gif)
There are a number of runes that have similar animations, or cost 50 Focus and seem more effective than some 100 Focus attacks. I think the above would help greatly with choosing what you want for your weapon.
Additionally, could there also be runes for shields?
It seems odd that raising the shield also switches to the rune icons in the bottom left, but of course nothing can be slotted in.
I personally think it would be nice to have runes like a shield bash, shield charge, projectile reflect, special counter, etc.