For crafting, I'd say Living Roots, Druid of the Saber, Mark of Y'Shaarj, Power of the Wild, and Druid of the Claw for sure. Those are all well rounded fast druid cards. If you already have the second Stranglethorn Tiger, Argent Squire, Defender of Argus, Darnassus Aspirant, Ancient of War, 1x Nourish, or Mire Keeper, definitely add those, but maybe don't craft them yet. There's also the free Enchanted Raven from the ONiK prologue.
After that, you'd probably want to give up on that deck altogether and netdeck a real druid deck, probably egg, token, or beast for the cheaper ones. I think egg is probably considered the best of the three at the moment, and is certainly the cheapest. It's a very synergistic deck though, so maybe hold off on taking too much from there unless you can build most of it.
http://www.hearthpwn.com/decks/691312-s33-j4ckiechans-egg-druid-mean-streets-of
Mounted Raptor is a bit of a bummer though, stuck two wings into an adventure that's rotating out soon. All of the faster druid decks like to use it.
EDIT: I should note that your deck probably isn't the only thing keeping you at rank 19, and there might be problems with crafting everything i mentioned if it makes your mana curve too low. I'm just starting with this deck myself and don't know everything. It's an experimental process, which is why i'm not crafting any cards until I feel i can dump it all into one great deck.
EDIT 2: Stupid Van Cleef and counterfeit coin stopped me from rank 15. Annoying how common these crazy turn 1 Van Cleefs are.
http://i.imgur.com/ZVqPgAv.jpg