Since Diablo 3 was updated to version 2.0, every single one of the character class skills was updated to perform an elemental damage type.
Unfortunately, due to the itemization in the game and the lack of non-fire-based items, as well as low damage outputs from non-fire-based skills, many of the game’s skills from the lightning, cold, holy, poison, arcane and physical builds perform rather poorly in contrast to their fire-based counterparts—at least in general.
Needless to say, skills with elemental damage aren’t as finely tuned as they could be, and Blizzard is well-aware of the situation.
One of the game’s community managers Nevalistis posted an update on the battle.net forums to assure players that the developers are looking at the skills, which may see a shift in elemental types in a future patch.
When we did a pass on elemental damage types across skills during the Closed Beta for Reaper of Souls, the Barbarian class was one that received the most revision. While we arrived at a place much closer to where we were aiming, we think there's room for some additional adjustments. I don't have details on exact changes to share at this time, but it's likely you'll see some skills, and not just for the Barbarian, shift around their elemental type in a future patch.
There’s no telling whether this patch will also bring better itemization to the game, so players can have an option besides wearing the Cindercoat or class-set armor for their chestpieces, for example.