Half elves and frankly ANY ranged class should never be able to do high 1-shot damage. They are RANGED and the fact that they can evade enemies while wearing them down / annoying them is their strength. Melee DPS classes are those that are expected to do heavy damage.
Half elves have plenty of damage in their skills with their high mobility and attack speed. they can do many smaller attacks without getting killed than those who are within melede striking reach.
If you can't survive being a half elf with the skills damage that they have now, you asre playing them wrong. Perhaps instead consider playing a melee or magic attack class.