I would suggest not only for all the demon weapons, valkor weapons, regal weapons, dryad event weapons,etc. that the +20 power etc. that they currently have be adjusted to equal or exceed the amount that a weapon crystal would give (Of the same tier).
Example: Demon Claw
has these stat bonuses on it:
+30 Strength
+30 Tooth&claw
these numbers match what a t6 tech would give the weapon assuming we crafted one, but are only about half what a socketed weapon with a t6 stat/ability crystal would give. A tier 4 stat crystal is +45 Strength, Tier 5 would be +55, tier 6: +65
Since that is somewhere between a tier 5 and tier 6 weapon, it should have between
+55 Strength, +55 Tooth&Claw and +65 Strength, +65 Tooth&Claw
Substitue the appropriate stat/skill on the other items like Bloodbow, Demon Flurry, Demon Axe, Mace of Divine Intervention, etc.