It's hard not to go overboard, isn't it? Who doesn't love a sunflower?!? I like the way you explored all the various angles here. I like the first and last one the best, though in the first one I would have liked seeing the complete tips of the bottom petals. A minor nitpick.
They are nice shots and angles, the light seems a little harsh so keep in mind that the best times to shoot are early morning and late afternoon. If that's not possible try get yourself a diffuser to soften the light
Still raining like stew. In a few minutes I'll have to go drain the pool a second time - took off 4 inches last time (a couple of hours ago) so it leaves me to have to entertain myself.... The first is a straight edit to remove the green color cast from the yellow petals and to give a little more definition to the center of the flower with some selective HSB adjustments and a bit of sharpening. The second is just a flight of my own fancy...dinking about to entertain myself. I really like sunflowers and like what you've done with these.