Let me play devil's advocate this time.
Okay, you've waited nearly two years for a Zac skin, seeing all the Annies, the Katarinas, the Ashes, the Braums, the Jinxs and the Lucians get new ones before you see one for your favorite champion.
Then, after all that waiting, they come out with... Blue Zac. A "simple" recolor of the classic skin. Would you get mad at all that waiting?
Even if you weren't that upset at the recolor, you'd probably get pissed at Rito's likely rationale:
"We know we said that we wanted to do justice to the long wait for a new Zac skin and we promised to make it worth the wait. However, in the end, we also knew that we needed to get something out to those fans who just wanted another option, so we're releasing this recolored skin and will continue to work on something worthy of Zac (but not nearly as hard)."
Also, this isn't the first time this has happened. When Soraka's first rework came out (back in 2012), there was a "Battle Priestess" skin announced. For reasons real, imagined, or made up, the skin was scrapped and out came... an homage to Final Fantasy's white mage. Believe me, many of us were pissed after waiting years for some Rito love only to get... that.
Also, Udyr players had nearly as long a wait for a new skin and they got Spirit Guard Udyr. Believe me, Soraka players were upset.
So, do you want something good or do you want something now?