Good job, but I just dont think the red on the front looks like blood, assuming thats what its supposed to be. Its a little to light for me, and not splattered in an apropriate way. Otherwise, a good solid job.
Btw, you do know you cant legally have khorne beserkers in an IW army, right?
This is a good starting point in becoming a good painter. Start trying out some shading/highlighting techniques to bring your painting along more. As it is now I can't see much in the way of highlights, with the exception of the skulls.