Hello there, here with some crit for ya
Composition/Blending You do rather well with making interesting compositions.

You use interesting pics and blend nicely. I like the different kinds of styles you've used throughout your gallery - it really shows off what you can do. Very interesting cuts on your icons. Your banners seem to all use that kind of placement of the girl's face being really big and all - it really looks nice in all of them, but try not to do all the same thing. Get just a little more variety in that section. Be careful when using a hard brush, it gets a little bit sloppy sometimes (like Fred/George's arm in the first banner).
Text Using less, I think, will help. That's what I do when I don't like the way my text looks

Your text gets kind of small in some of your graphics, so try not to make it so tiny it can't be read. Also, maybe try using a bit darker of colors so it stands out more. Other than that... you do a pretty nice job.
Coloring/Quality I like your use of one color to create unity in the graphic. That being said, I think it would give your graphics a lot more depth if you brought in some more colors. Just get a couple colors that still look nice together and I think you can still keep that unity but give your graphic a more... finished, I want to say... look. Additionally, try not to color faces too strongly - in the first banner, the pink on them is just a little too unnatural, I think. You've got a good grasp of image quality from what I can see - keep that up, it'll take you a long way

Mmmm... I think that's all I want to touch on, actually

You don't need a
lot of critique, really, because you're doing well. The main thing keeping you down, I think, is your smaller number of graphics. You have the potential for an awesome gallery - it just needs more in it!
Good luck with your graphics, dear, hope I helped