I think it looks good as is. If it keeps bothering you, you could tone it done one of two ways when you quilt it by either (1) picking either a 28 or 40wt
solid colored thread in that yellow-green hue behind the lion so you increase the amount of solid color in those sections, or (2) pick a 40 or 50wt red thread; since red & green are direct complements, the green will end up looking a bit greyish, thus toning it down (literally).
The other option would be to quilt it with a pale yellow thread so the yellow steals the attention & draws the viewer's eye to everywhere there is pale yellow in the quilt, rather than resting on the yellow-green batiks.
But regardless, it's a children's quilt & people aren't going to be focusing on the batiks anyways -- they're going to be looking at all the adorable animals & reading the cutesy sayings. So you really could do pretty much whatever you want with it & people will love it.
