Its nice, but too much empty space. Black and White is sick though. Work on not having as much empty space. other than that, keep at it!
For your first sprite use it's pretty decent. Although it's not original. I've seen this concept done many times with K, so it doesn't have a "wow" factor for me.
That's a pretty straight tag, buddy. The black and white version > The colored version in my opinion. The text could use some work / be taken out. Nice effects