AMUMU SKINS ARE OVERDATED

I have 4 Amumu skins which i all got from chests, and they all seem overdated as hell. I have PHARAOH, SAD KNIGHT, VANCOUVER, ALMOST-PROM KING and all suck. every skin is just a different character visual nothing else: no difference in abilities, no difference in voice, nothing. I think that riot could easy do a skin rework on Amumu because they are all pretty much the same. Only problem that i can think off is that he is such an underplayed champion that nobody gives a shit about him. Pls tell me your opinion.