Skins, Abilities' effects, and Abilities' icons

I hope this discussion can be seen because I am not sure where it will go after I create it. This is my first time of posting a discussion online I hope you find it interesting.

If I tried to explain what I want to talk about here, it will take too long to write. Therefore, the LINK I posted will make it easier for you to understand what the gist of my discussion is and for me to not write too much and make it boring to read.

As you see in the video, each skin of Morgana has different colors and effects. I guess what is only missing is that the abilities' icons change color or look from skin to skin. However, Why are these types of effects and color changes are not in all of the champions? such as Nunu, Ryze, i don't know who else... Ziggs maybe, Zed, etc. These changes would really make us want to play with the champions more and have more fun.

I guess abilities' icons would be a pain to change their colors and looks from skin to skin for each champion, but they would be AWESOME to see. Anyways, I really appreciate what Riot did and still doing for this game so far, and I am glad that I am playing League of Legends.