Like make it brighter, and/or show the range which 
can use it to his ally.
Right now, although is definitely a stronger champ than he was pre-rework, I honestly feel his passive is even more useless because I go entire games without using it (because allies go out of range and level up before I can)...
LaughingStapler1 votesI don't think he's better than pre rework at all. He was incredibly reliable then since bombs couldn't be dodged. Now he has better zone control and a more interesting kit but he's not stronger. He's just different.
Anyway, I'd love any change that will stop my allies from flashing away when I'm about to ult. them or have ulted them.
Sugar Momma1 votesHe is stronger honestly, his win rates across the board are up. Once you get used to landing the bombs they are actually pretty easy to land, the buffs over a few patches helped that. His AoE stun is so good.
In some ways he was better before, but I didn't mean for Zilean's overall power to be the focus of my post. Glad we can agree his passive is still lacking :^)
Saianna1 votesI hoped you'd say something like "make it usefull for a change", but oh well..
Sugar Momma1 votesI'd prefer this honestly but let's not ask for too much ;)