Pilots

Buzzfeed has a list, Here Are 35 First Episodes Of TV Shows That Will Hook You Instantly.

I agree with the ones I've watched (Barry, Schitt's Creek et al). Here's a few other pilots (that is, first episodes) that I consider to be particularly good/memorable.

TOP 10 (in no order):

The Cosby Show
Cheers
Fawlty Towers
Frasier
Friday Night Lights
The Sopranos
The Green Green Grass
The Mary Tyler Moore Show
Only Fools and Horses
The Vicar of Dibley

THE REST:

Blackadder
Black Books
Cuckoo
Fresh Prince of Bel-Air
Gavin and Stacey
The Wrong Man(s)
The Good Life
Green Acres
I'm Alan Partridge
The Inbetweeners
The IT Crowd
Lucky Louie
Malcolm in the Middle
All in the Family
Girls
The Office
WKRP in Cincinnati
Peep Show
Porridge
Roseanne
The Royle Family
Open All Hours
Veep
Wings
Yes, Minister