Why is there no Challenger skin this year? Also why didn't other Champ skins get the Riven treatment

1st) Ya where's our challenger skin this year.

Edit: Also should give Ahri/Nid the Riven treatment I go on to talk about on the 2nd part.

2nd) If you notice when someone plays Champ Riven, if they bought it when it came back last year it says "Championship Riven 2016".. If they had the original it has a cool boarder and has a II to stand for Season 2. Why didn't you do that for all the Champ skins. I want my Thresh and Shyv to have III and IV respectively. I didn't even buy Kali or Zed cause I can just buy it next year and no one would have any idea I didn't buy it apon release.