I think WW is the most balanced Rework to date.

Panth is beyond unbalanced. Did you not hear about his basically 100% ban rate at worlds?

Least overloaded? MAYBE, but a lot of earlier reworks would compete with that title.

Warwick is easily number 1, he's had some bugs but never been unbalanced.

The morde rework had a few parts that was too strong on release, but he hasn't been in patch notes for awhile now. I'm pretty sure he was in less patch notes than panth too.