Have you tried running a CD, offtanky support Zil with two strong close range killers? Aka Jax, Xin, olaf whomever you find good for 3s. I'm not in your elo, and I get he is cd dependant however hes able to give huge speed burst to champ for 5+ secs and or slow. His ability to augment teammates + dmg, and ult seems quite potent given expected team coordination. Even with random teammates, with the slightest preparation the speed burst and duration is a gauranteed gank or harass engagement. I guess what I'm missing is the obvious counter to Zil's ability to make those top tier champs far more effective, while still doing aoe dmg + any item activation one might want to use. Seems ridiculously strong and it is hard to counter a drastic movement speed defecit as opposing team unless you hug turret and even then you have Zil ult + speed augment to assist in diving faster and getting away safely.
I'll try and find some high elo 3s streams, figure it out for myself.