I never really liked the Bangle era BMW's, except maybe the 5 Series, but must admit they had to do something radical. After decades of refining design themes established by the 1970 Bertone BMW Garmisch 2002Ti concept their "language" had become very predictable. Not an accusation you can make of his time at BMW!
The news that he is leaving to "pursue his personal design-related endeavours beyond the auto industry" is a loss for BMW, but he leaves it in good hands.
One Chris Bangle design which has aged well, even become a bit of a classic, is a car I like so much I considered buying: the 1990's Fiat Coupe.
Perhaps it was the prototype for his "flame surfacing" concepts which later revolutionised BMW design.