The 3-series has been largely left untouched by the Bangle virus that affect BMW's design department and has evolved into a lovely little thing, with one exception. Its grille is horrible. And the short, sharp slope/bulge immediately above the grille makes it look like a sulking child that has puffed air into the space between its top lip and nose. Nasty.
The second best looking BMW of all time, behind the original 6-series, is the E28 5-series. Rich Scott's perfect example here demonstrates that BMW used to make the best grilles, and indeed entire front end, but have now descended into a designers wet dream, which is my idea of a nightmare.
I think the rot started with the Z4