i said this before, but whatever:
one option could be lowering cds so he can constantly speed up or not become useless when his bombs are on cd, bombs could also prioritize targets with bombs on them
#1
New Passive: Reminiscence
If Zilean stands still for 4 seconds he creates a Memory (a ghost of himself) (only 1 at the time, creating a new one eliminates others)
Memories cannot be target. Pressing Alt-key allows to control the memory (the original zilean can still be moved and damaged, like when controlling other clones) this memory looks "ghostly" and distinguishable from the original.
Memories don't grant vision and disappear after zilean dies.
Memories can't move but can cast spells with shared cooldown with the original.
4 seconds after of casting the first spell with a memory, the memory fades.
Now, memories could have 2 possible auras, either:
1- nearby allies get 8% extra XP.
2- when Zilean casts a spell, allied champions near the Memory get +5% cooldown reduction for X seconds and/or nerby enemies -5% cdr.
#2
New Passive: Reminiscence
Zilean creates a Memory after standing still for 5 seconds (an unkillable immobile ghost of himself).
Zilean can have a maximum of 1/2/3 Memories
When Zilean or any ally clicks on a Memory, it's teleported to it ((600 range) or 500/600/700) consuming the memory and granting Zilean some XP (regardless of who uses the Memory). (this would compensate for the XP/gold lost while Zilean is roaming and standing to leave the Memories)