Shooting type - Wear and tear + metal stuff.
Futuristic type - Glowing bits and flat areas with cool textures.
Futuristic shooter - Well... Some exposed wires, and some worn down cool textures maybe?
For now I don't know what constructive could be said about it. It seems to be a pretty early stage work, correct me if I'm wrong.
Make those gradients a bit softer (the bottom shouldn't be completely black). I'd say it has way too big color variation for a war game. You should stick to a chosen color scheme with one or maybe two colors (subtle/dark ones if the game is a bit more 'realistic' or 'hardcore'; dark+light color if the game is more of an Unreal Tournament-like action game). It's OK to color the HP/mana area, just be aware that the original warcraft3 text is colored too thus making the background light green while the text is light green might not end up well.