Visually confusing but nice stormy tone and activity. Emotions have been evoked.

It looks rather busy.
You shouldn't put smooth shading on lightning, because it doesn't look right T_T, and it needs to have sharper edges.
I cannot understand whats in bottom-right, it's too cluttered.
The desks debris which is flying around barely reminds me of desks.. It's hard to tell what that is. If only you put less black scratching and more highlights...
Needs more emphasizing of different objects, or this is also called staging. It means some things need to be darker, some brighter, and more of a line between background and foreground.