How can I improve my Dragon Deck?

To be honest, your deck does not seem to flow. I have had experience with decks that have a bunch of good random cards and find that they do work, but are too slow to be good in the new Yugioh format. Your deck, to be honest, would get destroyed in a tournament. I suggest you pick a theme and build a deck in that theme. Judging from your deck, I suggest you either choose a hopeless dragon, FGD, or Malefic deck. Start building on that.