I could go on four hours about Good Omens, so I'll just list a few things.

1. The Visual Effects.

   The visual effects are extraordinary, season 1 && season 2. My favorite bit of VA has to be season 2, before the beginning. Aziraphale && Angel Crowley. It was so brilliantly well done, and I'd love to see something like that done in season 3.

2. The actors.

   David Tennant and Michael Sheen did so so good at their respective roles, but how about the others? Jon Hamm did magnificent as the Archangel Fucking Gabriel. He really fits that role so good. And Jim? Oh man, Jim was the best season 2 character. ( Half Joking, of course )
   Anna Maxwell Martin doesn't get that much praise for her portrayal of Beelzebub, which is disappointing. I believe she did excellent! And so did Shelley Conn!
   Nina Sosanya and Maggie Service were delightful to have on the show TWO times! I really love Nina and Maggie as characters, and think they deserve a spot in season 3.
   And how could we ever for get Quelin Sepulveda's portrayal of Muriel? Literal ray of sunshine, and I love LOVE them. They're like my little child. (I'm Aziraphale, I adopted Them.)
   Of course, I love all the other actors too. They all did splendid.

3. The story.

   Yes, the story of season 1 is based off the book, and I won't go into much detail about that.. But it's a wonderful adaptation.
   Season 2's story absolutely broke me and I won't go into any detail of that either. Just know that you should stop watching by the time you get to those last 15 minutes, or you'll start bawling your eyes out.

Overall, Good Omens is a wonderful show that holds a special place in my heart. ( Psst, read the book as well. Archive.org has it if you don't want to buy a physical copy. )