I'd like another cute male yordle character, with a tragic story behind him. Maybe something revolving around sacrifice, possession, or obsession. Bonus points if he's Noxian, especially if he followed similar principles as Riven.
I imagine a grey furred yordle dashing through the night, running, escaping, and yet pursuing. He searches for something of power, something to make him recognized, something to earn his place in the city state. In the cover of night he finds something sinister, an entity also reaching out, seeking a willing vessel. An ethereal pact is forged, and turns it's attention towards the High Command, planning it's appearance, and it would seek both it's kin and retribution with interest.
I found inspiration for that in a few songs by Versa Emerge. In particular, I think Father Sky fits Swain, or some progeny of his, fairly well.