As posted here: "Effect & Focus" - Runes, Power Imbues & Sockets: Mechanic suggestion
I suggest changing the rune mechanic from “Trigger & Effect” to “Effect & Focus”
This will make effects always usable.
While at it, change the “runes” in d4 to be “Jewels” (Or “Charms”).
So we have Effect Jewels and Focus Jewels.
This frees runes to be the Consumable items mentioned in blog post - “consuming” a rune would be etching it to the weapon.
And now runes can also be merged to construct a more complex runes (Like in d2, but actually very different).