Cheshire Rengar: You know that cat from Alice in wonderland who becomes invisible and has this wide insane grin? That would make for an awesome Rengar skin! and it's so fitting too because Rengar becomes invisible too with his ult. There already are some other skins from the same theme, Mad hatter Shaco and Annie in wonderland so this would make a great addition in my opinion. Also, this could have LOTS of chromas.
Hazmat Yorick: Wearing a hazmat suit and wielding a shovel to bury toxic waste he summons mutated zombies that drip glowing green nuclear waste out of their mouths, his ult is a huge mutated monstrosity. I think zombies and toxic waste go very well together and the colors work for it well too. I'd love to see this skin.
Anyways, I just wanted to share this before I forget. Maybe whoever is creating these skins can draw some inspiration from this :)