Alright, so I just got my dark wind mage to 58 last night, and well to put it frank, the mage sucks. The 2 things this mage had going for it were, its ability to get in and out of combat, and its ability to destroy a single target, and with Rhys removing invisible it pretty much lost both, because he though it a good idea to also remove unholy aura.
Currently dark/wind moves as fast as a regular wind mage, which granted is faster then a regular mage, but its still not enough to do any real dodging, or fast enough to weave in and out of battle. For movement abilities, all it is left with now it Windwalk, which still sucks compared to crack. The build used to use invisible to sneak in (if there were no fire mages) assassinate the target and sneak out, if the enemy acted slow enough (which in groups of 3+ you almost never got out alive) Now you have no way to get close to the target w/o an icy orb up ur ass. Sure they can kill a single target 9 times outta 10, but they have almost no means to use any of their skills because of the range restrictions. I realize you removed invisible from the books for balance purposes, but you really just killed a mediocre class, where as fire lightning, can just crack in ur face and kill you with 2 stomps. I honestly don't see how it is fair.
tl;dr put the dark/wind m-book back to the way it was. It sucks now.