I'd say that in this current iteration and patch, he's probably one of the very few fair and balanced champions. And for once, I'm not using those words sarcastically. FeelsGoodMan.
But it's actually even more than just fair and balanced. He's also diverse, being able to be built AP or tank, being able to take almost any sensible keystone for either role, including predator, he's one of the only champions without a straight up "build this exact way or lose effectiveness" feel to him.
If I play Pantheon, I need Electrocute. If I play Zac, I should probably run Aftershock. If I play Nunu...should I take Predator? Grasp? Comet? Should I try making a variant with Spellbook or Phase Rush? I've seen almost anything work on him outside of conqueror, tempo, HoB and PTA. And I love the diversity.