Since it's your first wallpaper, let me advice you a few things.

First, your signature is preferred to be in the bottom right corner of the wallpaper, however anywhere on the bottom is nice too, but on the top is not so good since it will take a chunk out of the whole wallpaper ~.~

Another thing is that you should always explain what you did to accomplish your work, and if possible, include links to the scan, brushes, fonts, etc etc.

Well ... with that said, let's move on to evaluate your wallpaper n_n

First of all, I love the colors, purple is one of my fav colors
The scan of Suigintou is a very nice one as well ... it's a shame you didn't include a link to it >_<
The bright white spots on her standout rather nicely, very nice work with that too.

The background, looks very nice and very well done.
There are members that say she doesn't fits with the background's concept ... but the concept is the waller's choice ... so I won't be complaining there :P

Overall, very good first wallpaper, you did a decent job with it n_n
Nice work and I expect to see even better wallpapers from you in the nearby future x]
Keep them coming!