It has no relation whit this, but if you could go
there to help Catox (look at the bottom of the thread), he's got an English question
For your knight :
He's rather good. The knight seems a bit stiff (?) but, hey, he's a knight.
That aside, the horse's head is way too big, with too small ears.
For the backgroud... I don't know. It really depend on the mood you want to express... Cause you know that a knight armor is really reflecting, so whatever background you choose, il will had an impact on the colors of the knight (if you want it to look good)... so first you choose the mood, then the color, then the backgroud, I think.