His bombs are much more satisfying to use, by turning it into a skillshot they have been able to significantly extend the cast range, give him a potential AOE stun, and allow him to zone by putting them on the ground and makes for some pretty interesting baits.
What angers me is that they reduced the damage on his bombs on his rework, but they are buffing the damage on his bombs next patch.
Overall I think the Zilean rework was for the better, some of the numbers are slightly undertuned but they have the theme of his kit nailed down.