Kayle Rework
With all these old champs getting remade I wanna talk about something real with yall for a sec. Kayle. 
Kayle was my first champ in league and it seems like she has kinda fallen by the wayside. She seems like she is still a strong champ in her own right but early mana costs and a last luster skill set are holding her back in my opinion. While it would be easy just to turn her into a ranged mage I think it'd be cool to go more of the route that Riot took with Nidalee and focus on the personality and abilities on the champion.
It seems like the only reason that Kayle can't use righteous fury all the time is to give opponents an opportunity for counterplay and while the flame sword is an iconic part of Kayle's kit it'd be nice to see some versatility between switching from flame sword to regular sword. Maybe put her into a more supporty role and make her E a passive but allow her to swap between damage and auto attacking teammates for healing.
Maybe in "ranged" form reckoning could remain a slow but in "melee" form it could turn into a root.
Maybe divine blessing could apply some sort of mark to allied champions adding some bonus magic damage to their attacks.
Kayle's skill set is already pretty support oriented and while I'd be sad to see her nuke potential get hit I'd much rather people start playing her again.
Also please bring back her old dance... I'm begging you >.>