OK I hate to be a jerk but those models are ugly lol..
A default blockhead's head put into a brick with kaje's skull decal would be better than that :V
First problem being it's huge compared to the actual blockhead... Skulls are a tad smaller than the full head, not bigger. The jaw should also be smaller than the above skull. Tony is also very right, just because you think it looks better as a perfect cube, you need to keep it accurate to the blockhead or it is going to look stupid (like it does now). Also what is that odd cornering you put on it? It looks like a big fluffy pillow now, it doesn't resemble a blockhead skull at all.