As others have said, I would only add another border if you just absolutely needed it to be larger.
With that said, I think this is one of the most adorable quilts I've seen in a long while!! The cat(s), the sunflower(s), and the poem take the quilt from "ordinary"... almost "ho-hum" (I'm not a fan of "house" quilts) to "how can I enlarge this shot so I can find the cat and the sunflower?" extraordinary!!
You (or your guild) should make this up as a pattern and sell it. Even though I'm not a "house quilt" person, I'd buy it just because it's so darn cute!!!