Let's see. Background is something that ruins to moment. I guess you should choose a texture that is not that big and can repeat normally, although the best way is to put a simple color. White border around forum icons make the contrast too much. You should use custom image navigation bar, not the one with text, it will look more elegant. And banner doesn't really have any amazing effects. You should work on your text and choose one subject (Harry, Ron etc, or text). Work on your fonts and text effects. Other than that, is fine, just your banner width should be same as forum width so you won't have that blank space between forum's edges and banner. Use percent width only for phpbb3 skins when banner blends with gradient behind it so it's auto extended till the end. In phpbb2 you should use banner with a 1px stroke (same color as forum border) and width same as forum. And by the way, footer shouldn't be changed or forum may be banned.

Hope you like the comments.

A truly wonderful skin...

I like those temes! <3<3<3<3

'Love it!

Love that skin, but hate the mouse. I changed it, but already forgot, how to. My friend choosed this skin too, but we can't find where we can change the cursor... Is it allowed to help here? I'd like to know, where this changing place was.

Anyways, it's a wonderful skin!

A simple theme, but for Harry Potter skin it's not bad.

I agree wih Gassy Try something advanced.
P.S: I'm a fan of Harry Potter ( 10+ for idea )