I ADORE Harold & Maude. Need to rewatch it.
Bernie is one that I never seem to see mentioned anywhere, but it's delightful in every way.
The actors who played the kooky east Texas characters were fantastic.
Also:
I'm a Cyborg But That's OK (2006)
The House of Yes (1997)
And I've seen a number of mumbly existential indie comedies on Netflix but most were forgettable. Can't recommend them.
I'm tempted to mention the Angels in America mini-series (based on the play of the same name) though it's not quite a comedy.