I have a deck very similar to this deck and i found that increasing savagery works better than natures blessing because it hase a flashback cost. http://www.mtgvault.com/ViewDeck.aspx?DeckID=407941 my verson of the +1/+1 counter deck idea
Permalink
There are better green/black lands than golgari guildgate. you could try overgrown tomb or woodland cemetery
mana flare could help you since most dragons are pumpable
curse of exaustion
you could replace the seedborn muse with quest for renewal.
the chosen really just take up space and they have no abilities. besides nissa's other ability is far better.
semblence anvil may work
1 noble heirarch and 1 oblivion ring ring possibly
Whispersilk cloak?
you could add some unblockable creatures or whispersilk cloaks so your one champion is unblockable