What is my deck missing ?

Get rid of the black and red aspects of this deck, they really do not do anything for it. You also do not have enough lands, 22 would be a good number not 18. Llanowar Elves is a must here, I suggest also running Nissa Rivane (the planeswalker) and Nissa's Chosen to combo with Eldrazi Monument. Coat of Arms and Darksteel Forge do not fit very well in this deck.