With a lot of low cost creatures and a lot of land gain, I would reccomend to put in a Khalni Hydra if you can find one. I have a similar deck and I know that Bellowing Tanglewurm is a powerfull asset as well.
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There's but 1 weakness to the creatures: Flying. Your deck does not have any of it. And the only way to evade your spells would be via counterspell like cards. So, in short, a blue control deck would be your weakness. Protection from [color] and minion spam would be annoying too. Maybe some low-cost flyers would enhance this deck.