In response to this following post in the forums.. http://us.battle.net/d3/en/forum/topic/8568988912?page=1#16
The permanent up time is not the main problem with these skills, and I would like to point out that while in archon form, you are quite limited in skills. You still need to drop out of archon to re-cast, and if you remove this feature of archon, you would completely kill the build, and reduce the already low amount of viable builds in the game for the wizard. The other point is, a wizard can just swap over to a Chantodo's wand, and just proc the critical mass passive to refresh the cooldown anyways, so you end up just making it inconvenient.
Also, comparing Wrath of the Berseker and Archon in the same manner is pointless, given that you are very limited in what skills you can use while in archon, while the barbarian still has full use of their skill selection while in wrath. If you want to make some meaningful change, maybe consider making WOTB more like Archon in the way the skills are different while in that form.
With that in mind, then the real problem is Wrath of the Berserker, but there are several elements that make this skill so overpowered, and by the looks of it, the community and the developers don't have a real grasp of the "actual" problem. The main problem is not that you can keep it up indefinitely with Thrive on Chaos rune, nor is it the buff in DPS output and movement speed. Those bonuses I have accepted, and while they could be toned down a bit, the real problem with the skill is not those two aspects of Wrath, but that you are permanently immune to any crowd controlling effects, and that is the real issue with wrath. So the problem is the barbarian itself lacks any other hard CC break. So if we are to fix the problem, we need to shift this completely broken ability mechanic and move it to another skill, either via Leap, Overpower or a War Cry of some sort. Then you can drop CC immunity from WOTB completely, and maybe even keep it around as a way to break CC on initial cast, but while in Wrath, the player is no longer immune. That alone I feel will bring a bit of balance back to the class. Yes it is a nerf, but I think a lot of players would agree that this one is needed.