Particles are fine. In games, particle effects could be done a variety of ways, so whichever way you want to, is fine.

One thing about textures. Right now, it kinda seems as if you're pretty much grabbing a photo source, and simply using it as the texture straight up. Nothing wrong with a photo source, but it'd be good if you could manipulate them in photoshop. Add weathering, stains, mold, dust, etc etc.