First Vector Submission rejected, unsure why

I’m not entirely sure why my vector design was rejected. I wish there more in-depth reason other than ‘significant improvements and changes’ needed.

I did submit the vector to the Vector category. Does anyone know, from experience, what GraphicRiver requirements are for submitting vector designs.

My design is below. http://imgur.com/1K3wo

I quite like the quality of the vectors, but I think the way you have composed the image doesn’t look that good. Maybe you could make it like a crest with symmetrical wheat plants at either side, like on the Erdinger beer logo or something like that. Just an idea.