If you are thinking about the sunflower idea.....
https://www.pinterest.com/pin/307652218264636764/
I think it could be neat to put a big yellow sun in one corner with long rays reaching out and the sunflowers down in the opposite corner reaching up towards the sun with a lot of leaves.
I do agree with the others that if you change out the border, putting at least a dark blue stopper border, then add your other border back to the quilt and have it quilted professionally, you might like it more. I don't like a lot of mine until I get them quilted. Then they look a lot better.