I think it doesn't make sense that all the skills that add elemental damage to your weapon work with ranged weapons, but one important one does not work with melee weapons, namely Elemental Arrowshead.
This leads to the situation that it is perfectly viable to create a ranger that stacks wits (instead of Finesse), Intelligence (for more elemental damage) and Geomancer (instead of Warfare or Huntsman) and uses Elemental Arrowhead, Siphon Poison, Venom Coating/Venomous Aura and Firebrand. You can see a further explanation of this build
here.
If you want to do the same for melee, you're out of luck. Elemental Arrowhead doesn't work with melee weapons. Although you can cast it on them, it has no effect. While it makes sense that this spell only works with bows/x-bows, it just seems unfair that the others all work with ranged weapons and stack. Ranged weapons are extremely powerful already and this is a another situation where they are straight up superior to any melee weapon.
In my opinion, Elemental Arrowhead should either work with melee weapons as well or Venom Coating/Venomous Aura should not work with bows/x-bows. A third options would probably be just to disable the stacking of Elemental Arrowhead and Venom Coating/Venomous Aura so you can't use them at the same time at least.
In my opinion the first option would be preferable. All other options would just reduce your options while this one would increase them.
