Love the angel theme, its a shame Wizards hasn't printed more low cost angels. On that note, you absolutely need 24 lands. Decks that run 20 either have a ton of creature based ramp, Birds of Paradise, Sylvan Caryatid, Courser of Kruphix etc...or can operate well with only 3-5 mana for the entire game, or both.
If you want to make the deck more consistent, I would try to specify what you want the deck to do. Do you want to focus purely on the angel theme? It wouldn't be competitive but I love tribal decks in casual. In that case consider more consistent cards (lower cmc) like Bladed Bracers, Emancipation Angel, Luminarch Ascension.
I would consider going up to 3/4 Herald of War and experimenting with ways to get more counters on her quickly. If you want to make a deck that can get big angels out quickly, she's your best bet.
Defy Death is good thematically, great for your theme, and works excellently with Herald of War.
Angelic Overseer is a great beater if you want to go the more Human/Angel theme route, which it looks like you're working towards.
Your other option if you really want to make this competitive would be to go full on red/white aggro, which consists mainly 1-3 cmc creatures with haste that give each other bonuses. That will end up getting away from your angel theme however.
February 9, 2015 1:30 p.m.
I'm wanting to keep the 3 big angels in. I have been seriously considering putting in 4 more land. I want to make it more competitive. Luminarch looks like a great card that I will need to look in to.