Deck help, black/white angel demon deck

[DGnephilim]

Looking for advice on my black white angel and demon deck. So far it is focused on Entering the battlefield effects and life gain.

Deck list:
Instants
-Doom blade x2
-Bile blight x1
-Cloudshift x2
-Go for the throat x1
-Riot control x1
-Gravepurge x1
-Coat with venom x1

Sorcerys
-Drown in sorrow x1
-Read the bones x1
-Sign in blood x1
-Despise x1

Creatures
-Cathedral sanctifier x4
-Restoration Angel x2
-Serra avenger x1
-Oreskos sun guide x1
-Herald of war x1
-Master of the feast x1
-Archangel of thune x1
-Herald of torment x1
-Typhoid rat x1
-Precinct captian x1
-Rune-Scarred Demon x1
-Lord of the void x1
-Indulgent tormentor x1
-Seraph of dawn x1

Artifacts
-Elixir of immortality x1
-Whip of erebos x2

Enchantments
-Infernal scarring x1

Planeswalker
-Elspeth, Suns champion

Land
-Plains x10
-Swamps x10
-Seraph Sanctuary x2
-Scoured barrens x2

All advice and suggestions welcomed. Have played casually and done well with this deck so far, however I feel like it has room for improvement. Looking into lightkeeper of emeria, orzhov guildmage, shattered angel, morbid plunder, grasp of darkness, and demon lord of ashmouth. Thanks so much for any help