The reason he breaks items so often is because he gets autoattacks at a safe range without any counterplay, even if you hop at him, as he'll just hop away as well. He never is in any danger, and can harass as long as he can work around enemy minions.
However, I'd say both his Q and E are iconic, maybe even whole kit at this point. W is a bit wonky, but I can't see parting with it.
I'd take it in one of two directions, myself:
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Drop Q range substancially, maybe even about Cait AA range, but change W to extend his range if he hits a champion with it.
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Keep as is, but make W instead place charge on his target that gives the cooldown reduction of his current Q.
Both of these would probably require some improved damage on his Q's, but at least it'd give opponents counterplay measures. I'd say the first is the least invasive in lategame gameplay, and therefore a better choice overall, but both will need some refining, for sure.