Blizzard will never win with this formula, they will never plaese everyone. Even if, like someone suggested, legendaries were only utility, there will be few of them more powerful then others, even by a small %.
And the whine will start again and again. The only or the most "fair" solution is the WoD and MoP system.
P.S: i don't mind this legendary system, i don't agree with whiners that say "i can't kill stuff without BiS legend". I only think this system is a bit frustrating for someone who want to switch specs.