If you are a beginner, I would consider you rather mediocre. All of your banners are rather plain and empty, with nothing particularly eye catching save for the render. Your renders themselves look slapped on, though I can't say too much without being hypocritical. Try brushing over them or erasing part of them to blend them into the background, though you first have to have some more effects to help you blend the renders in in the first place. Changing the transparency in a particular area doesn't always help to blend it it, or at least, not on its own, you might want to try blurring a few areas to bring focus to the areas of the banner where you want people to notice. I'll skip the text because I suck at text, so I really wouldn't be able to write anything about the text. Your banners also seem to be very similar in terms of style as well, with a background of diagonally slanting stroke things, or a solid color brushed over with brushes with a lower opacity. I would suggest you try some variation, mostly in your backgrounds, and maybe download some brushes (almost always helps). Also read a few tutorials, they really do help you to improve at graphics, and you can always add your own spin to it. Just keep practicing (hypocritical, cause I'm a beginner), its the only way to really get better.