This is the final version of "Just Say Yes." As you can see I've added more nature elements while maintaining contrast between "just say yes" and the background grass.
In addition I've made the sneakers more visible/interesting: their colors pop more, they have a distinct shadow, and the details are simpler.
Finally, the composition has changed slightly: In this version, the onlooker is closer to the grass, closer to the words "just say yes", which gives more focus to the words and also makes it feel like the Converse-d person is *just* about to 'say yes' and go play on the grass (or whatever he/she might be about to do).
The image dimensions are with a Facebook cover photo in mind. If it goes up, I'll link to the Facebook page here :)