Any way of changing my deck to be better (its a Warrior/spellcaster deck)?

Warriors and Spellcasters do not work very well together. Choose one or the other, not both. There are plenty of good support cards for both types and you can get most of them from theme decks. Only having one copy of 90% of the cards in the deck is a really bad idea because you will never be able to draw what you need when you need it.