The colours look great, and their both eye-catching and bright. But you could spice up the font with more colour, add some textures, layer things up a bit, and make the borders a bit fancier. And also, the text looks a bit squished in the first one (try making the font smaller so it fits better) and the banners could be more professional looking. If you can, I'd say the backgrounds could be slightly paler, so the text stands out more, but I'm guessing that you used paint, where you can't do some of these things.