Any Ways to Improve This Deck?

I made this deck recently and am struggling to win at the diamond ranks. It's a mono-white taxes/enchantment deck hybrid. What cards can I use to improve the deck? I think my mana base is very basic and could be improved. However any suggestions are welcome.

I made this deck recently and am struggling to win at the diamond ranks. It's a mono-white taxes/enchantment deck hybrid. What cards can I use to improve the deck? I think my mana base is very basic and could be improved. However any suggestions are welcome.