That many wallpapers? I will try and help you, but honestly I think you should not post that many at the same time.
It's a bit overhelming for those who want to help...
Okay I have seen every of your "wallpapers". I don't want to hurt your feelings, but they actually look
like screenshots. Every single one of them looks rather blurry. Making a wallpaper is more than that. I don't
really know how to help you to improve the "wallpapers" that you showed here. So I will try to give you some
hints about making wallpapers. And hopefully this will help you.
When you want to make a wallpaper, first of all you need to have a nice scan to work with. So I suggest, browse the
Gallery here on MT for lovely scans, don't use any screenshots from Anime unless you know how to improve their
quality.
When you make wallpapers there are most often two options. You either have a scan in excellent quality that can be used
for your wallpaper and only has to be extracted. That is like "taking it out" from it's usual background
so that you can work with it on Photoshop. That other option is making a vector. For this you need to know how to use
the pen tool on Photoshop.
So if you are using Photoshop what I would suggest now is to learn to use the pen tool for either extraction or
vectoring. I learned it with help of the Pen tool tutorial by Kuroimisa. You can find it here on the site of the
Underappreciated Group: http://theunderappreciated.minitokyo.net/.
Next thing is to make a nice background that also fits to the original art of the scan. And it is not enough here either
to simply use a photo and place the vector or extracted scan on it... But that's so much to talk about... you need
to go step by step. So I again suggest to look at the pen tool. Spend some time with Photoshop and you will find out how
many things you can do there. It's like a new universe I think. ;)
Hope I didn't sound harsh... I was trying to help and sometimes you need to give an honest opinion. Have fun
exploring photoshop! :)